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Biomedical subjects

Frederick P Li

Publications and source records attributed to Frederick P Li.

At least 19 recordsLinked to original sources
PubMed2006

Asian American Network for Cancer Awareness, Research, and Training's legacy. The first 5 years.

The Asian American Network for Cancer Awareness, Research, and Training (AANCART) is the first special populations network for Asian Americans on a national basis and includes collaborating organizations from Boston, New York, Houston, Seattle, San Francisco, Los Angeles, Hawaii, and Sacramento (where it is headquartered at the University of California, Davis). NCI funding of AANCART in 2000 brought together investigators and leaders from 9 cities across 6 states to establish an infrastructure for addressing cancer awareness, research, and training. Since 2000, AANCART has conducted needs assessments, held community awareness activities and trainings, trained trainees, sponsored National Asian American Cancer Control Academies, and produced presentations, publications, and grants. All specific aims have been attained, including the establishment of an infrastructure to promote Asian American cancer awareness, research, and training in 4 targeted regions; the establishment of partnerships to promote accrual to clinical trials, training, and pilot studies; and the formulation and successful implementation of grant-funded research to reduce the cancer burden among Asian Americans. AANCART's first 5 years have increased cancer awareness, trained special populations scientists, and advanced the field of Asian American cancer control research. Cancer 2006. (c) 2006 American Cancer Society.

Asian↗
PubMed2006

A process evaluation of a telephone-based peer-delivered smoking cessation intervention for adult survivors of childhood cancer: the partnership for health study.

OBJECTIVE: We report on the process evaluation of an efficacious national smoking cessation intervention for adult survivors of childhood cancer. We examine associations between intervention implementation characteristics and study outcomes, as well as participant characteristics related to level of involvement in the intervention. METHODS: The study was conducted at the Dana-Farber Cancer Institute in Boston, Massachusetts, from 1999-2001. Participants (n = 398) were randomly assigned to receive a proactive telephone-based peer counseling intervention. They received up to 6 counseling calls, individually tailored and survivor-targeted materials, and nicotine replacement therapy (NRT) patches if they were prepared to quit smoking. RESULTS: Forty-two percent of survivors participated in the maximum number of calls (5-6), and 29% of participants requested and received NRT. Total counseling time was an average of 51 min. Quit status at follow-up was related to intervention dose, and participants who received NRT were significantly more likely to make a 24-h quit attempt. Demographic variables (females, White), higher daily smoking rate, poorer perceived health and moderate perceived risk of smoking were significantly related to greater intervention involvement. CONCLUSIONS: A brief peer-delivered, telephone counseling intervention is an effective way to intervene with adult survivors of childhood cancer who are smoking. Findings from the process evaluation data (call length and number, frequency, and spacing) will inform future telephone counseling cessation programs.

Adult↗
PubMed2006

Prevalence of early onset colorectal cancer in 397 patients with classic Li-Fraumeni syndrome.

BACKGROUND & AIMS: Hereditary colorectal cancer is associated most commonly with the hereditary nonpolyposis colorectal cancer or familial adenomatous polyposis syndromes. We investigated the prevalence of early onset colorectal cancer and the frequency of p53 germline mutations in 64 families from a Li-Fraumeni syndrome (LFS) registry. METHODS: Patients with documented colorectal cancer and a diagnosis at or before age 50 were included. P53 analyses were performed through germline mutational analyses using standard molecular techniques. RESULTS: Among the 397 patients and 64 families in the classic LFS registry, a total of 11 patients (2.8%) from 10 different families (15.6%) met criteria for classic LFS and had documented colorectal cancer at less than 50 years of age. The mean age at diagnosis in this group was 33 years and of these patients 4 developed colorectal cancer before age 21 (ages, 9, 11, 15, and 20 y). All families that were tested for p53 mutations (8 of 10) had evidence of germline mutations by sequence analysis; therefore, 12.5% of the total number of families in the registry had colorectal cancer at age less than 50 years and a documented germline p53 mutation. Mutations primarily were missense or nonsense and were located between exons 4-10. CONCLUSIONS: LFS patients with germline p53 mutations may have an increased susceptibility to colorectal cancer and present up to several decades earlier than the general population. LFS should be considered when a young patient presents with colorectal cancer.

Adult↗
PubMed2006

Breast and ovarian cancer in relatives of cancer patients, with and without BRCA mutations.

BACKGROUND: First-degree relatives of patients with breast or ovarian cancer have increased risks for these cancers. Little is known about how their risks vary with the patient's cancer site, carrier status for predisposing genetic mutations, or age at cancer diagnosis. METHODS: We evaluated breast and ovarian cancer incidence in 2,935 female first-degree relatives of non-Hispanic White female patients with incident invasive cancers of the breast (n = 669) or ovary (n = 339) who were recruited from a population-based cancer registry in northern California. Breast cancer patients were tested for BRCA1 and BRCA2 mutations. Ovarian cancer patients were tested for BRCA1 mutations. We estimated standardized incidence ratios (SIR) and 95% confidence intervals (95% CI) for breast and ovarian cancer among the relatives according to the patient's mutation status, cancer site, and age at cancer diagnosis. RESULTS: In families of patients who were negative or untested for BRCA1 or BRCA2 mutations, risks were elevated only for the patient's cancer site. The breast cancer SIR was 1.5 (95% CI, 1.2-1.8) for relatives of breast cancer patients, compared with 1.1 (95% CI, 0.8-1.6) for relatives of ovarian cancer patients (P = 0.12 for difference by patient's cancer site). The ovarian cancer SIR was 0.9 (95% CI, 0.5-1.4) for relatives of breast cancer patients, compared with 1.9 (95% CI, 1.0-4.0) for relatives of ovarian cancer patients (P = 0.04 for difference by site). In families of BRCA1-positive patients, relatives' risks also correlated with the patient's cancer site. The breast cancer SIR was 10.6 (95% CI, 5.2-21.6) for relatives of breast cancer patients, compared with 3.3 (95% CI, 1.4-7.3) for relatives of ovarian cancer patients (two-sided P = 0.02 for difference by site). The ovarian cancer SIR was 7.9 (95% CI, 1.2-53.0) for relatives of breast cancer patients, compared with 11.3 (3.6-35.9) for relatives of ovarian cancer patients (two-sided P = 0.37 for difference by site). Relatives' risks were independent of patients' ages at diagnosis, with one exception: In families ascertained through a breast cancer patient without BRCA mutations, breast cancer risks were higher if the patient had been diagnosed before age 40 years. CONCLUSION: In families of patients with and without BRCA1 mutations, breast and ovarian cancer risks correlate with the patient's cancer site. Moreover, in families of breast cancer patients without BRCA mutations, breast cancer risk depends on the patient's age at diagnosis. These patterns support the presence of genes that modify risk specific to cancer site, in both carriers and noncarriers of BRCA1 and BRCA2 mutations.

Adult↗
PubMed2005

Health insurance coverage in survivors of childhood cancer: the Childhood Cancer Survivor Study.

PURPOSE: To examine the prevalence and predictors of health insurance coverage and the difficulties obtaining coverage in a large cohort of childhood cancer survivors. PATIENTS AND METHODS: This study included 12,358 5-year survivors of childhood cancer and 3,553 sibling controls participating in the Childhood Cancer Survivor Study. Data were collected by surveys distributed in 1994 (baseline) and 2000 (follow-up). RESULTS: At baseline, 83.9% of adult survivors, compared with 88.3% of siblings, had health insurance coverage (P < .01); 6 years later, small but significant survivor-sibling differences remained (88% v 91%; P < .01). Twenty-nine percent of survivors reported having had difficulties obtaining coverage, compared with only 3% of siblings (P < .01). In multivariate analysis of survivors 18 years of age or older, factors associated with being uninsured included younger age at diagnosis (diagnosis age of 0 to 4 years; odds ratio [OR] = 1.7; 95% CI, 1.3 to 2.2), male sex (OR = 1.3; 95% CI, 1.2 to 1.5), age at baseline survey (age 22 to 24 years; OR = 1.6; 95% CI, 1.2 to 2.1), lower level of attained education (less than high school, OR = 2.6, 95% CI, 2.1 to 3.3; high school graduate, OR = 2.1, 95% CI, 1.8 to 2.5), income less than 20,000 dollars (OR = 5.6, 95% CI, 4.5 to 7.1), marital status (widowed/divorced/separated; OR = 1.3; 95% CI, 1.1 to 1.6), smoking status (current smoker, OR = 2.0, 95% CI, 1.7 to 2.3; former smoker, OR = 1.4, 95% CI, 1.2 to 1.8), and treatment that included cranial radiation (OR = 1.3, 95% CI, 1.0 to 1.6). CONCLUSION: Compared with siblings, adult survivors of childhood cancer had significantly lower rates of health insurance coverage and more difficulties obtaining coverage. Since lack of coverage likely has serious health and financial implications for this at-risk population, any disparity in availability and quality of coverage is of great concern.

Adolescent↗
PubMed2005

Peer-delivered smoking counseling for childhood cancer survivors increases rate of cessation: the partnership for health study.

PURPOSE: Cancer survivors smoke at rates that are only slightly lower than the general population. This article reports on the final outcomes of Partnership for Health, a smoking cessation intervention for smokers in the Childhood Cancer Survivors Study (CCSS). METHODS: This study is a randomized control trial with follow-up at 8 and 12 months that involved smokers (n = 796) enrolled onto the CCSS cohort. Participants were randomly assigned to either a self-help or a peer-counseling program that included up to six telephone calls from a trained childhood cancer survivor, tailored and targeted materials, and free nicotine replacement therapy. The intervention was delivered by telephone and postal service mail. RESULTS: The quit rate was significantly higher in the counseling group compared with the self-help group at both the 8-month (16.8% v 8.5%; P < .01) and 12-month follow-ups (15% v 9%; P < or = .01). Controlling for baseline self-efficacy and readiness to change, the intervention group was twice as likely to quit smoking, compared with the self-help group. Smoking cessation rate increased with an increase in the number of counseling calls. The cost of delivering the intervention was approximately 300 dollars per participant. The incremental cost-effectiveness of the intervention compared with controls was 5,371 dollars per additional quit. CONCLUSION: Interventions to prevent future illnesses are of critical importance to childhood cancer survivors. The Partnership for Health intervention resulted in a doubling of smoking cessation quit rates. Because of the seriousness of smoking among childhood cancer survivors, this intervention model may be appropriate as a multicomponent treatment program for survivors who smoke.

Adolescent↗
PubMed2005

The extract of huanglian, a medicinal herb, induces cell growth arrest and apoptosis by upregulation of interferon-beta and TNF-alpha in human breast cancer cells.

Huanglian (Coptidis rhizoma), a widely used herb in traditional Chinese medicine, has been shown recently to possess anticancer activities. However, the molecular mechanism underlying the anticancer effect of the herb is poorly understood. Specifically, whether huanglian extract affects the expression of cancer-related genes has not been defined. This study used DNA microarray technology to examine the effect of the herbal extract on expression of the common genes involved in carcinogenesis in two human breast cancer cell lines, the ER-positive MCF-7 and ER-negative MDA-MB-231 cells. Treatment of the cancer cells with huanglian extract markedly inhibited their proliferation in a dose- and time-dependent manner. The growth inhibitory effect was much more profound in MCF-7 cell line than that in MDA-MB-231 cells. DNA microarray assay revealed that treatment with huanglian dramatically increased the mRNA expression of interferon-beta (IFN-beta) and tumor necrosis factor-alpha in MCF-7 cells. Quantitative analysis by real-time PCR or western blotting confirmed the upregulation of the two genes (especially IFN-beta) in MCF-7 cells, but not in MDA-MB-231 cells. Addition of neutralizing antibody against IFN-beta to culture medium markedly inhibited the huanglian-induced antiproliferative effect, confirming the involvement of IFN-beta in the huanglian's effect and also suggesting an autocrine pathway for the action of IFN-beta in this setting. Given that IFN-beta is among the most important anticancer cytokines, the upregulation of this gene by huanglian is, at least in part, responsible for its antiproliferative effect. The results of this study implicate huanglian as a promising herb for chemoprevention and chemotherapy of certain cancers.

Apoptosis↗
PubMed2005

Familial gastrointestinal stromal tumor syndrome: phenotypic and molecular features in a kindred.

PURPOSE: Members of a family with hereditary gastrointestinal stromal tumors (GISTs) and a germline KIT oncogene mutation were evaluated for other potential syndrome manifestations. A tumor from the proband was analyzed to compare features with sporadic GISTs. PATIENTS AND METHODS: Members of a kindred in which six relatives in four consecutive generations comprised an autosomal dominant pattern of documented GISTs and cutaneous lesions underwent physical examination, imaging studies, and germline KIT analysis. A recurrent GIST from the proband was studied using microarray, karyotypic, immunohistochemical, and immunoblotting techniques. RESULTS: In addition to evidence of multiple GISTs, lentigines, malignant melanoma, and an angioleiomyoma were identified in relatives. A previously reported gain-of-function missense mutation in KIT exon 11 (T --> C) that results in a V559A substitution within the juxtamembrane domain was identified in three family members. The proband's recurrent gastric GIST had a 44,XY-14,-22 karyotype and immunohistochemical evidence of strong diffuse cytoplasmic KIT expression without expression of actin, desmin, or S-100. Immunoblotting showed strong expression of phosphorylated KIT and downstream signaling intermediates (AKT and MAPK) at levels comparable with those reported in sporadic GISTs. cDNA array profiling demonstrated clustering with sporadic GISTs, and expression of GIST markers comparable to sporadic GISTs. CONCLUSION: These studies provide the first evidence that gene expression and mechanisms of cytogenetic progression and cell signaling are indistinguishable in familial and sporadic GISTs. Current investigations of molecularly targeted therapies in GIST patients provide opportunities to increase the understanding of features of the hereditary syndrome, and risk factors and molecular pathways of the neoplastic phenotypes.

Adult↗
PubMed2005

Risk of new cancers after radiotherapy in long-term survivors of retinoblastoma: an extended follow-up.

PURPOSE: Many children diagnosed with retinoblastoma (Rb) survive into adulthood and are prone to subsequent cancers, particularly hereditary patients, who have germline Rb-1 mutations. We have extended the follow-up of a large cohort of Rb patients for 7 more years to provide new information on the risk of additional cancers after radiotherapy in long-term survivors. PATIENTS AND METHODS: We analyzed the risk of new cancers through 2000 in 1,601 Rb survivors, diagnosed from 1914 to 1984, at two US medical centers. The standardized incidence ratio (SIR) was calculated as the ratio of the observed number of cancers after hereditary and nonhereditary Rb to the expected number from the Connecticut Tumor Registry. The cumulative incidence of a new cancer after hereditary and nonhereditary Rb and radiotherapy was calculated with adjustment for competing risk of death. RESULTS: Subsequent cancer risk in 963 hereditary patients (SIR, 19; 95% CI, 16 to 21) exceeded the risk in 638 nonhereditary Rb patients (SIR, 1.2; 95% CI, 0.7 to 2.0). Radiation further increased the risk of another cancer in hereditary patients by 3.1-fold (95% CI, 2.0 to 5.3). Hereditary patients continued to be at significantly increased risk for sarcomas, melanoma, and cancers of the brain and nasal cavities. The cumulative incidence for developing a new cancer at 50 years after diagnosis of Rb was 36% (95% CI, 31% to 41%) for hereditary and 5.7% (95% CI, 2.4% to 11%) for nonhereditary patients. CONCLUSION: Hereditary Rb predisposes to a variety of new cancers over time, with radiotherapy further enhancing the risk of tumors arising in the radiation field.

Brachytherapy↗
PubMed2005

Oral contraceptive use and risk of early-onset breast cancer in carriers and noncarriers of BRCA1 and BRCA2 mutations.

BACKGROUND: Recent oral contraceptive use has been associated with a small increase in breast cancer risk and a substantial decrease in ovarian cancer risk. The effects on risks for women with germ line mutations in BRCA1 or BRCA2 are unclear. METHODS: Subjects were population-based samples of Caucasian women that comprised 1,156 incident cases of invasive breast cancer diagnosed before age 40 (including 47 BRCA1 and 36 BRCA2 mutation carriers) and 815 controls from the San Francisco Bay area, California, Ontario, Canada, and Melbourne and Sydney, Australia. Relative risks by carrier status were estimated using unconditional logistic regression, comparing oral contraceptive use in case groups defined by mutation status with that in controls. RESULTS: After adjustment for potential confounders, oral contraceptive use for at least 12 months was associated with decreased breast cancer risk for BRCA1 mutation carriers [odds ratio (OR), 0.22; 95% confidence interval (CI), 0.10-0.49; P < 0.001], but not for BRCA2 mutation carriers (OR, 1.02; 95% CI, 0.34-3.09) or noncarriers (OR, 0.93; 95% CI, 0.69-1.24). First use during or before 1975 was associated with increased risk for noncarriers (OR, 1.52 per year of use before 1976; 95% CI, 1.22-1.91; P < 0.001). CONCLUSIONS: There was no evidence that use of current low-dose oral contraceptive formulations increases risk of early-onset breast cancer for mutation carriers, and there may be a reduced risk for BRCA1 mutation carriers. Because current formulations of oral contraceptives may reduce, or at least not exacerbate, ovarian cancer risk for mutation carriers, they should not be contraindicated for a woman with a germ line mutation in BRCA1 or BRCA2.

Adult↗
PubMed2004

Ganoderma lucidum extracts inhibit growth and induce actin polymerization in bladder cancer cells in vitro.

This study was conducted to investigate chemopreventive effects of Ganoderma lucidum using a unique in vitro human urothelial cell (HUC) model consisted of HUC-PC cells and MTC-11 cells. Ethanol and water extracts of fruiting bodies and spores of the G. lucidum were used to examine growth inhibition, actin polymerization status, and impact of actin remodeling on cell migration and adhesion. Results showed that ethanol extracts had a stronger growth inhibition effect than water extracts. Cell cycle analysis showed that the growth inhibition effect was associated with G2/M arrest. At non-cytotoxic concentrations (40-80 microg/ml), these extracts induced actin polymerization, which in turn inhibited carcinogen 4-aminobiphenyl induced migration in both cell lines. The increased actin polymerization was associated with increased stress fibers and focal adhesion complex formation, however, expression of matrix metalloproteinase-2 and focal adhesion kinase (total and phospholated) were unchanged, which suggests that other mechanisms may be involved.

Actins↗
PubMed2004

Multiple risk behaviors among smokers in the childhood cancer survivors study cohort.

The literature on health behaviors of young adult cancer survivors is very limited, and thus little is known about preventable risk factors in this population. This paper describes the prevalence of five behavioral risk factors among 541 young adult survivors of childhood cancers from the CCSS cohort who were identified as smokers and enrolled in a randomized controlled trial of a smoking cessation intervention. The relationship between presence of multiple risk factors and a number of smoking-related factors was examined. About 31% of the sample engaged in zero or one health-risk behavior in addition to smoking; 63% engaged in 2 or 3, and 6% engaged in 4 or 5. There were positive linear relationships between number of risk factors and smoking rate and nicotine dependence. Number of risk factors was not associated with self-efficacy for quitting, but was related to readiness to quit. This study demonstrated that childhood cancer survivors who smoke have a number of other risk factors for the development of preventable disease and the presence of these risks was associated with factors that decrease the likelihood of quitting smoking. Attention to other health behaviors may be an important strategy for helping smokers quit. In particular, helping childhood cancer survivors who smoke to reduce other risk behaviors might also encourage them to quit smoking.

Adolescent↗
PubMed2004

Accuracy of cancer family histories: comparison of two breast cancer syndromes.

Cancer risk programs rely on accurately reported family history information. This study compares the accuracy with which cancer sites and ages at diagnosis are reported by Li-Fraumeni syndrome (LFS) and hereditary breast-ovarian cancer syndrome (HBOCS) families undergoing genetic testing. We analyzed the accuracy of 191 cancer diagnoses among first-degree (FDRs) and second-degree (SDRs) relatives reported by 32 LFS and 52 HBOCS participants in genetic testing programs. Cancer diagnoses of relatives were more accurately reported in the HBOCS cohort (78%) than in the LFS cohort (52%). Almost all breast cancer diagnoses were accurately reported, whereas 74% of ovarian cancer diagnoses and only 55% of other LFS-related cancers were accurately reported. Age at diagnosis was accurate within 5 years for 60% of LFS relatives and 53% of HBOCS relatives. Factors correlating with accurate reporting of cancer history included: being member of BRCA1 family, higher education level, female historian, degree of closeness to affected relative, and having fewer than 5 affected FDRs and SDRs. Relying on verbal histories would not have altered eligibility for genetic testing among HBOCS historians, but fewer than half of LFS historians provided information that would have led to TP53 testing. Our data suggest that it may not be necessary to confirm breast cancer diagnoses routinely; however, documentation of other cancer types remains important for appropriate risk assessment and follow-up.

Age Factors↗
PubMed2004

Ganoderma lucidum spore extract inhibits endothelial and breast cancer cells in vitro.

This study was conducted to investigate the anti-proliferative activities of medicinal mushroom Ganoderma lucidum (Rei-shi or Mannentake). We have identified an alcohol extract from the spore of Ganoderma lucidum that inhibits the in vitro proliferation of human umbilical vein endothelial cells and MDA-MB231 human breast cancer cells. Further fractionation of the alcohol extract revealed that the ethyl acetate fraction inhibited both cell lines in a dose-dependent manner from 2 to 40 micro g/ml. Our results suggest that the alcohol extract from the spore of Ganoderma lucidum may possess potential anti-tumor and anti-angiogenic activities.

Angiogenesis Inhibitors↗
PubMed2004

Prevalence of BRCA1 mutation carriers among U.S. non-Hispanic Whites.

Data from several countries indicate that 1% to 2% of Ashkenazi Jews carry a pathogenic ancestral mutation of the tumor suppressor gene BRCA1. However, the prevalence of BRCA1 mutations among non-Ashkenazi Whites is uncertain. We estimated mutation carrier prevalence in U.S. non-Hispanic Whites, specific for Ashkenazi status, using data from two population-based series of San Francisco Bay Area patients with invasive cancers of the breast or ovary, and data on breast and ovarian cancer risks in Ashkenazi and non-Ashkenazi carriers. Assuming that 90% of the BRCA1 mutations were detected, we estimate a carrier prevalence of 0.24% (95% confidence interval, 0.15-0.39%) in non-Ashkenazi Whites, and 1.2% (95% confidence interval, 0.5-2.6%) in Ashkenazim. When combined with U.S. White census counts, these prevalence estimates suggest that approximately 550,513 U.S. Whites (506,206 non-Ashkenazim and 44,307 Ashkenazim) carry germ line BRCA1 mutations. These estimates may be useful in guiding resource allocation for genetic testing and genetic counseling and in planning preventive interventions.

Adult↗
PubMed2003

Older Asian Americans and Pacific Islanders dying of cancer use hospice less frequently than older white patients.

PURPOSE: Cancer is the leading cause of death among Asian Americans, yet little is known about their use of hospice care. We examined hospice use by Asian patients compared with white patients, and assessed whether utilization differs among those born in the United States or abroad. METHODS: We studied Asian and white Medicare beneficiaries registered in the Surveillance, Epidemiology, and End Results (SEER) Program who died of primary lung, colorectal, prostate, breast, gastric, or liver cancer between 1988 and 1998. We used logistic regression to determine the effects of race/ethnicity and birthplace on hospice use, adjusting for demographic characteristics, managed care insurance, year of diagnosis, tumor stage at diagnosis, and tumor registry. RESULTS: Of the 184,081 patients, 5% (n = 8614) were Asian Americans, of whom 45% (n = 3847) were foreign born. Compared with whites, Asian Americans were more likely to be male, married, and enrolled in managed care. Compared with U.S.-born Asian Americans, foreign-born Asian Americans were more likely to reside in low-income areas. After adjustment, patients who were Asian American (odds ratio [OR] = 0.67; 95% confidence interval [CI]: 0.62 to 0.73) and born abroad (OR = 0.90; 95% CI: 0.86 to 0.94) were less likely to use hospice care than were white patients. These results were consistent across the six cancer diagnoses that were examined. CONCLUSION: Older Asian Americans dying of cancer, especially those who are born abroad, are less likely than white patients to use hospice care at the end of life. Additional research is needed to understand the reasons for these differences and to eliminate potential barriers to hospice care.

Age Factors↗