American Cancer Society

About: American Cancer Society is a nonprofit organization based out in Atlanta, Georgia, United States. It is known for research contribution in the topics: Cancer & Population. The organization has 1339 authors who have published 3700 publications receiving 688166 citations. The organization is also known as: American Cancer Society, ACS & American Society for the Control of Cancer.

Molecular pathology of primary and metastatic ductal pancreatic lesions: analyses of mutations and expression of the p53, mdm-2, and p21/WAF-1 genes in sporadic and familial lesions.

Abstract: BACKGROUND The molecular pathology underlying the development and progression of ductal pancreatic adenocarcinoma is poorly understood relative to that of other major cancers in industrialized societies. The frequency, nature, and distribution of p53 abnormalities, their temporal relationship to the metastatic and clinicopathologic phenotypes of sporadic and familial pancreatic cancer, and their consequent effects on the genetics and expression of critical wild-type p53-regulated genes (mdm-2 and p21/WAF-1) warrant examination in pancreatic adenocarcinoma. This molecular and immunochemical study of the p53, mdm-2, and p21/WAF-1 genes and gene products examined the largest series of nonneoplastic, neoplastic, and metastatic ductal pancreatic lesions reported to date in relation to clinicopathologic profile. METHODS Histologically confirmed specimens of primary (n = 136) and metastatic (n = 23) sporadic and familial ductal pancreatic adenocarcinoma lesions were subjected to immunochemical analyses of p53 expression in which a panel of 3 antibodies was utilized. A panel of nonneoplastic but histologically abnormal pancreatic lesions (n = 77) from individuals with varied histories of cigarette smoking were subjected to similar immunohistochemical examinations. In addition, 3 specimens from patients with chronic pancreatitis, 2 specimens of normal fetal pancreata, and 16 specimens of normal adult pancreata were examined as control tissues. Suitable frozen and archival microdissected tumor lesions were evaluated for mutations in exons 4-9 of the p53 gene by single strand conformation polymorphism (SSCP) and dideoxy sequencing analyses in which two distinct sets of outer and nested intron-based amplification primers were used for each exon. A subset of 25 tumor specimens and 18 tumor-derived cell lines for which the p53 mutation status was known were examined for amplification and/or overexpression of the mdm-2 gene; amplification was determined by Southern hybridization and overexpression by immunohistochemical and Western blot analyses. Similarly, mutations in the coding region of p21/WAF-1 gene were examined by SSCP and DNA sequence analyses, and steady-state expression of the p21/WAF-1 protein was assessed by Western blot analysis in these subsets of tumors and tumor-derived cell lines. RESULTS Positive ductal nuclear p53 immunostaining was demonstrated in 56% of primary tumors and 54% of metastatic lesions. The frequency did not differ significantly between sporadic and familial lesions, and immunostaining was not observed in ductal, acinar, or islet cell elements of normal pancreata or histologically abnormal benign pancreatic lesions from cigarette smokers. A total of 70% of tumor samples revealed reproducible SSCP abnormalities for p53; 42% of these were found in exons 7 and 8. DNA sequence analysis of cases with greater than 35% epithelial cellularity (n = 25) revealed 17 missense mutations, 12 of which were transitions. Seventy-five percent of these transitions were of G:CA:T type. A total of 22% of the p53 mutations identified were microdeletions, along with one insertional mutation at exon 8. None of the normal pancreata from sporadic or familial lesions revealed germ-line p53 alterations. Moreover, the frequency and spectra of p53 alterations exhibited no clear, statistically significant association with tumor grade, TNM stage, or patients' cigarette-smoking histories. The mdm-2 gene was neither amplified nor overexpressed immunochemically in a subset of ductal adenocarcinomas, and there was no clear relationship between the p53 mutation status and the status of the mdm-2 gene or protein. Similarly, SSCP and DNA sequence analysis of the p21/WAF-1 gene revealed only 2 genetic abnormalities in a series of 25 primary tumors and 15 tumor-derived cell lines; 1 of the cell lines also revealed the absence of immunoreactive p21/WAF-1 protein. CONCLUSIONS This immunochemical and molecular study of the p53 tumor suppressor gene/protein and the p53-regulated genes mdm-2 and p21/WAF-1 in this series of ductal pancreatic lesions revealed that p53 mutations are a frequent early event in pancreatic tumorigenesis not associated with metastatic progression. The authors observed complex spectra of transition missense mutations and microdeletions but no significant correlation with tumor grade, TNM stage, or smoking history. In contrast, amplification and overexpression of the mdm-2 gene/protein and genetic abnormalities in the p21/WAF-1 gene are infrequent events in the development of ductal pancreatic adenocarcinoma and were not clearly associated with the p53 mutation status of tumors examined in this study. Cancer 1997; 79:700-16. © 1997 American Cancer Society.

Vitamin E supplements and risk of prostate cancer in U.S. men.

Abstract: Supplementation with alpha-tocopherol (a form of vitamin E) was associated with decreased risk of prostate cancer in a randomized trial among Finnish smokers. We examined the association between vitamin E supplement use and prostate cancer incidence in the Cancer Prevention Study II Nutrition Cohort. Participants in the study completed a detailed questionnaire at enrollment in 1992-1993. Historical information was also available from a questionnaire completed in 1982 at enrollment in a previous cohort. Through August 31, 1999, we documented 4,281 cases of incident prostate cancer among 72,704 men. Multivariate-adjusted rate ratios (RRs) were calculated using Cox Proportional Hazards models. Regular vitamin E supplement use (>/=4 times per week) was not associated with overall risk of prostate cancer or with risk of advanced prostate cancer at diagnosis. No trend was seen with increasing dose of vitamin E. Men who reported regular vitamin E use in both 1982 and in 1992-1993 were not at lower risk of prostate cancer. Among current smokers, there was a suggestion of slightly reduced risk with regular vitamin E supplement use [RR = 0.87, 95% confidence interval (CI) = 0.67-1.11]. Our results do not support an important role for vitamin E supplements in prostate cancer prevention.

Recreational Physical Activity and Leisure-Time Sitting in Relation to Postmenopausal Breast Cancer Risk

Abstract: Epidemiologic evidence supports an inverse association between physical activity and postmenopausal breast cancer. Whether associations exist for moderate activities, such as walking, and whether associations differ by estrogen receptor (ER) status, body mass index (BMI, kg/m(2)), adult weight gain, or use of postmenopausal hormones (PMH) is unclear. The relation between time spent sitting and breast cancer also is unclear. Among 73,615 postmenopausal women in the American Cancer Society Cancer Prevention Study II Nutrition Cohort, 4,760 women were diagnosed with breast cancer between 1992 and 2009. Extended Cox regression was used to estimate multivariable-adjusted relative risks (RR) of breast cancer in relation to total recreational physical activity, walking, and leisure-time sitting. Differences in associations by ER status, BMI, weight gain, and PMH use were also evaluated. The most active women (those reporting >42 MET-hours/week physical activity) experienced 25% lower risk of breast cancer than the least active [0-<7 MET-hours/week; 95% confidence interval (CI), 0.63-0.89; Ptrend = 0.01]. Forty-seven percent of women reported walking as their only recreational activity; among these women, a 14% lower risk was observed for ≥7 hours/week relative to ≤3 hours/week of walking (95% CI, 0.75-0.98). Associations did not differ by ER status, BMI, weight gain, or PMH use. Sitting time was not associated with risk. These results support an inverse association between physical activity and postmenopausal breast cancer that does not differ by ER status, BMI, weight gain, or PMH use. The finding of a lower risk associated with ≥7 hours/week of walking may be of public health interest.

Human papillomavirus vaccination 2020 guideline update: American Cancer Society guideline adaptation.

Abstract: The American Cancer Society (ACS) presents an adaptation of the current Advisory Committee on Immunization Practices recommendations for human papillomavirus (HPV) vaccination. The ACS recommends routine HPV vaccination between ages 9 and 12 years to achieve higher on-time vaccination rates, which will lead to increased numbers of cancers prevented. Health care providers are encouraged to start offering the HPV vaccine series at age 9 or 10 years. Catch-up HPV vaccination is recommended for all persons through age 26 years who are not adequately vaccinated. Providers should inform individuals aged 22 to 26 years who have not been previously vaccinated or who have not completed the series that vaccination at older ages is less effective in lowering cancer risk. Catch-up HPV vaccination is not recommended for adults aged older than 26 years. The ACS does not endorse the 2019 Advisory Committee on Immunization Practices recommendation for shared clinical decision making for some adults aged 27 through 45 years who are not adequately vaccinated because of the low effectiveness and low cancer prevention potential of vaccination in this age group, the burden of decision making on patients and clinicians, and the lack of sufficient guidance on the selection of individuals who might benefit.