Scd1 and monounsaturated lipids are required for autophagy and survival of adipocytes

OBJECTIVE

Exposure of adipocytes to 'cool' temperatures often found in the periphery of the body induces expression of Stearoyl-CoA Desaturase-1 (Scd1), an enzyme that converts saturated fatty acids to monounsaturated fatty acids. The goal of this study is to further investigate the roles of Scd in adipocytes.

METHOD

In this study, we employed Scd1 knockout cells and mouse models, along with pharmacological Scd1 inhibition to dissect the enzyme's function in adipocyte physiology.

RESULTS

Our study reveals that production of monounsaturated lipids by Scd1 is necessary for fusion of autophagosomes to lysosomes and that with a Scd1-deficiency, autophagosomes accumulate. In addition, Scd1-deficiency impairs lysosomal and autolysosomal acidification resulting in vacuole accumulation and eventual cell death. Blocking autophagosome formation or supplementation with monounsaturated fatty acids maintains vitality of Scd1-deficient adipocytes.

CONCLUSION

This study demonstrates the indispensable role of Scd1 in adipocyte survival, with its inhibition in vivo triggering autophagy-dependent cell death and its depletion in vivo leading to the loss of bone marrow adipocytes.

SCD1 and monounsaturated lipids are required for autophagy and survival of adipocytes

Exposure of adipocytes to 'cool' temperatures often found in the periphery of the body induces expression of Stearoyl-CoA Desaturase-1 (SCD1), an enzyme that converts saturated fatty acids to monounsaturated fatty acids. In this study, we employed Scd1 knockout cells and mouse models, along with pharmacological SCD1 inhibition, to investigate further the roles of SCD1 in adipocytes. Our study reveals that production of monounsaturated lipids by SCD1 is necessary for fusion of autophagosomes to lysosomes and that with a SCD1-deficiency, autophagosomes accumulate. In addition, SCD1-deficiency impairs lysosomal and autolysosomal acidification resulting in vacuole accumulation and eventual cell death. Blocking autophagosome formation or supplementation with monounsaturated fatty acids maintains vitality of SCD1-deficient adipocytes. Taken together, our results demonstrate that in vitro inhibition of SCD1 in adipocytes leads to autophagy-dependent cell death, and in vivo depletion leads to loss of bone marrow adipocytes.

Impact of Treatment Modality on Quality of Life Among Uterine Cancer Survivors

AIMS

Our understanding of the impact of adjuvant therapy on longitudinal quality of life (QoL) following surgery for patients with uterine cancer is limited. The purpose of this study was to compare QoL in patients who have undergone surgery with or without radiation therapy for uterine cancer.

MATERIALS AND METHODS

This was a cross-sectional cohort study that examined women treated for uterine cancer at MD Anderson Cancer Center from 2006 to 2017. Participants included those who underwent hysterectomy/bilateral salphingo-oophorectomy alone, with brachytherapy or external beam radiation therapy (EBRT). A non-cancer cohort of women who underwent a hysterectomy/bilateral salphingo-oophorectomy for benign indications was also identified (non-CA). To compare QoL we used the Functional Assessment of Cancer Therapy - Endometrial survey (FACT-En), a validated survey used to assess QoL. The survey has five subscales: physical, social, emotional, functional and an endometrial cancer-specific subscale. Cohorts were compared using ANOVA tests.

RESULTS

In total, 309 women responded to the questionnaire (hysterectomy/bilateral salphingo-oophorectomy 64, brachytherapy 77, EBRT 96, non-CA 72). The median time from surgery to survey completion was 6.7 years. The mean total FACT-En score for the entire cohort was 144 [standard deviation 22]. Overall QoL was different between cohorts, with the EBRT cohort reporting the lowest QoL (mean 139.4 [21.6]) and the brachytherapy cohort the highest (150.6 [18.2], P = 0.006). Among patients who had undergone cancer treatment, the EBRT cohort reported the worst endometrial-specific QoL (53.5 [8.6]), while again the brachytherapy group reported the highest score (57.5 [6.1], P = 0.007).

CONCLUSIONS

QoL differences in women who have undergone different treatments for uterine cancer may persist years after treatment. In women with endometrial cancer who require adjuvant therapy, brachytherapy does not appear to have any long-term detriments on QoL.

The molecular and metabolic program by which white adipocytes adapt to cool physiologic temperatures

Although visceral adipocytes located within the body's central core are maintained at approximately 37°C, adipocytes within bone marrow, subcutaneous, and dermal depots are found primarily within the peripheral shell and generally exist at cooler temperatures. Responses of brown and beige/brite adipocytes to cold stress are well studied; however, comparatively little is known about mechanisms by which white adipocytes adapt to temperatures below 37°C. Here, we report that adaptation of cultured adipocytes to 31°C, the temperature at which distal marrow adipose tissues and subcutaneous adipose tissues often reside, increases anabolic and catabolic lipid metabolism, and elevates oxygen consumption. Cool adipocytes rely less on glucose and more on pyruvate, glutamine, and, especially, fatty acids as energy sources. Exposure of cultured adipocytes and gluteal white adipose tissue (WAT) to cool temperatures activates a shared program of gene expression. Cool temperatures induce stearoyl-CoA desaturase-1 (SCD1) expression and monounsaturated lipid levels in cultured adipocytes and distal bone marrow adipose tissues (BMATs), and SCD1 activity is required for acquisition of maximal oxygen consumption at 31°C.

Abstract P4-20-05: Patient-reported cosmetic outcomes in older breast cancer survivors: A population-based survey study

Background: For older women with breast cancer, local therapy options may include (1) lumpectomy followed by whole breast irradiation (Lump+WBI), (2) lumpectomy followed by brachytherapy (Lump+Brachy), (3) lumpectomy followed by endocrine therapy alone without radiation (Lump alone), (4) mastectomy without radiation (Mast alone), or (5) mastectomy followed by radiation (Mast+RT). For many patients, several of these options are acceptable based on current guidelines, but little is known about the impact of treatment choice on long-term cosmetic outcomes. We surveyed a population-based cohort of older breast cancer survivors treated with 1 of these 5 options to assess patient satisfaction with cosmetic outcome.

Methods: We used nationally comprehensive Medicare claims to identify women age ≥67 diagnosed with non-metastatic breast cancer in 2009, treated with 1 of these 5 treatment options, and still alive in 2015. From this cohort, 1650 patients (330 patients per local therapy) were randomly selected. Of these, 397 opted out, and the remaining 1253 potential participants were mailed a survey that included the CanSORT Satisfaction with Breast Cosmetic Outcomes instrument (5-point scale, higher score indicates greater satisfaction) and the Breast-Q Satisfaction with Breast instrument (0-100 Rasch transformed score, higher score indicates greater satisfaction). Multivariable linear regression models were used to assess the association of local therapy with each outcome, adjusting for age, race, comorbidity, chemotherapy, patient-reported BMI, bra cup size, smoking, income, and education. Spearman's correlation assessed the relationship between the 2 outcomes. All analyses incorporated sample and response weights.

Results: We received completed surveys from 498 women (30% response rate). The median age was 73 years (range, 67-87 years). The interval from diagnosis to survey was 6 years for all patients. Among patients with evaluable CanSORT responses (n=439), the weighted mean score by treatment group was 3.64 for Lump+WBI, 4.01 for Lump+Brachy, 3.83 for Lump alone, 3.28 for Mast alone, and 3.25 for Mast+RT. In multivariable analysis with Lump+WBI as the referent, the adjusted CanSORT mean score was 0.37 points higher for Lump+Brachy (P=0.009), 0.35 points lower for Mast alone (P=0.035), and 0.33 points lower for Mast+RT (P=0.048). Among patients with evaluable Breast-Q Satisfaction responses (n=418), the weighted mean score by treatment group was 60.9 for Lump+WBI, 68.8 for Lump+Brachy, 66.7 for Lump alone, 58.8 for Mast alone, and 52.0 for Mast+RT. In multivariable analysis with Lump+WBI as the referent, the adjusted Breast-Q Satisfaction score was 7.4 points higher for Lump+Brachy (P=0.03) and 7.8 points lower for Mast+RT (P=0.04). Higher comorbidity predicted worse cosmetic outcome in both models; no other variables were associated with both outcomes. The 2 outcomes were highly correlated (Spearman's coefficient=0.8, P<0.0001).

Conclusion: In this nationally representative cohort, satisfaction with cosmetic outcome (as measured by 2 distinct instruments) was higher for patients treated with Lump+Brachy and lower for those treated with Mast+RT compared to Lump+WBI. These results may be used to inform patient treatment decisions.

Citation Format: Swanick CW, Lei X, Xu Y, Shen Y, Goodwin NA, Giordano SH, Hunt KK, Jagsi R, Shaitelman S, Peterson SK, Smith BD. Patient-reported cosmetic outcomes in older breast cancer survivors: A population-based survey study [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-20-05.

Screening adherence and cancer risk perceptions in colorectal cancer survivors with Lynch-like syndrome

Cancer screening recommendations for patients with Lynch-like syndrome (LLS) are not well defined. We evaluated adherence to Lynch syndrome (LS) screening recommendations, cancer risk perceptions, and communication within the families among colorectal cancer (CRC) survivors with LLS. Thirty-four participants with LLS completed a questionnaire about risk perception, adherence to LS screening recommendations, and communication with relatives. Clinical data were obtained from medical records. Most participants (76%) believed they should undergo colonoscopy every 1-2 years. Only 41% correctly interpreted their genetic tests as uninformative negative or as variant of unknown significance for LS. Less than half had had an upper gastrointestinal endoscopy for screening purpose. Among female participants, 86% had been screened for endometrial cancer (EC) and 71% for ovarian cancer. Most participants had informed relatives about the CRC diagnosis and advised them to undergo CRC screening, but only 50% advised female relatives to be screened for EC and only one-third advised relatives to have genetic counseling. Most CRC survivors with LLS follow the same cancer screening recommended for LS patients but do not understand the meaning of LLS. Greater care must be devoted to communicating the implications of nondiagnostic germline mutation testing among patients with LLS.

Communication and technology in genetic counseling for familial cancer

When a cancer predisposing germline mutation is detected in an index case, the presence of the underlying syndrome is confirmed and the potential for predictive testing of at-risk relatives is established. However, the reporting of a positive family history does not routinely lead to communication of information about risk to close, much less distant relatives. This review summarizes information technology utilized to address penetration or 'reach' of knowledge of risk within extended families, including the use of telephone and video counseling to reach distant patients, and anticipate novel internet-based processes for communication between investigators and relatives.

Gynecologic cancer screening and communication with health care providers in women with Lynch syndrome

We evaluated knowledge of gynecologic cancer screening recommendations, screening behaviors, and communication with providers among women with Lynch syndrome (LS). Women aged ≥25 years who were at risk for LS-associated cancers completed a semi-structured interview and a questionnaire. Of 74 participants (mean age 40 years), 61% knew the appropriate age to begin screening, 75-80% correctly identified the recommended screening frequency, and 84% reported no previous screening endometrial biopsy. Women initiated discussions with their providers about their LS cancer risks, but many used nonspecific terms or relied on family history. Most were not offered high-risk screening options. While many women were aware of risk-appropriate LS screening guidelines, adherence was suboptimal. Improving communication between women and their providers regarding LS-related gynecologic cancer risk and screening options may help improve adherence.

Changes in screening behaviors and attitudes toward screening from pre-test genetic counseling to post-disclosure in Lynch syndrome families

The purpose of this study was to examine colonoscopy adherence and attitudes toward colorectal cancer (CRC) screening in individuals who underwent Lynch syndrome genetic counseling and testing. We evaluated changes in colonoscopy adherence and CRC screening attitudes in 78 cancer-unaffected relatives of Lynch syndrome mutation carriers before pre-test genetic counseling (baseline) and at 6 and 12 months post-disclosure of test results (52 mutation negative and 26 mutation positive). While both groups were similar at baseline, at 12 months post-disclosure, a greater number of mutation-positive individuals had had a colonoscopy compared with mutation-negative individuals. From baseline to 12 months post-disclosure, the mutation-positive group demonstrated an increase in mean scores on measures of colonoscopy commitment, self-efficacy, and perceived benefits of CRC screening, and a decrease in mean scores for perceived barriers to CRC screening. Mean scores on colonoscopy commitment decreased from baseline to 6 months in the mutation-negative group. To conclude, adherence to risk-appropriate guidelines for CRC surveillance improved after genetic counseling and testing for Lynch syndrome. Mutation-positive individuals reported increasingly positive attitudes toward CRC screening after receiving genetic test results, potentially reinforcing longer term colonoscopy adherence.

Communication of BRCA1 and BRCA2 genetic test results to health care providers following genetic testing at a tertiary care center

Individuals at high risk for hereditary cancers often receive genetic counseling and testing at tertiary care centers; however, they may receive care for long-term management of their cancer risk in community settings. Communication of genetic test results to health care providers outside of tertiary care settings can facilitate the long-term management of high risk individuals. This study assessed women's communication of BRCA1/BRCA2 genetic test results to health care providers outside of tertiary care settings (termed "outside" health care providers, or OHCPs) and women's perceptions regarding communication of results. Women (n = 312) who underwent BRCA1/BRCA2 genetic counseling and testing completed a questionnaire assessing whether or not they shared test results with OHCPs and perceptions regarding the communication of test results to OHCPs. Most (72%) shared genetic test results with OHCPs. Women with no personal history of cancer were more likely to have shared results compared to women with a personal history of cancer. Mutation status did not significantly predict sharing of genetic information. Most reported positive perceptions regarding the disclosure of genetic test results to OHCPs. The majority did not report any concerns about potential insurance discrimination (88%) and indicated that OHCPs were able to appropriately address their questions (81%). Although most women shared their genetic test results with OHCPs, those with a personal history of cancer may need further encouragement to share this information. Tertiary care centers should facilitate outreach and education with OHCPs in order to assure appropriate long-term cancer risk management for high risk populations.

Attitudes and beliefs about environmental hazards in three diverse communities in Texas on the border with Mexico

OBJECTIVE

Since communicating risk related to environmental hazards has consistently presented a challenge to government agencies and industries, our objective was to better understand the attitudes and beliefs of three communities, so as to help agencies and industries develop better risk communication interventions.

METHODS

We explored attitudes and beliefs about environmental risks in three diverse communities in Texas on the border with Mexico, in the county of El Paso. During the summer of 1995, using a door-to-door survey, we interviewed 147 individuals, using a questionnaire based upon an existing instrument. Interviews were conducted in three very different areas of the county: semirural low-income, urban low-income, and suburban upper-income. We randomly selected specific sections in each of the three communities for inclusion in the sample. We assessed attitudes and beliefs about regulations and experts, risk and hazards, and how to address environmental issues.

RESULTS

Attitudes and beliefs varied among the three communities, especially in the assessment of riskiness of various hazards. In general, there was mistrust of government agencies and of industries, a strong feeling that the environment can be improved, and a lack of understanding about what actions individuals might take to improve the environment.

DISCUSSION

Agencies need to find ways to increase their credibility with the public, and they should assess communities in order to understand the attitudes of the residents.

Oncology nurses' knowledge, practice, and educational needs regarding cancer genetics

This study evaluated oncology nurses' knowledge of cancer genetics and related topics, and identified current practice patterns and perceived educational needs in this area. A 54-item study questionnaire was mailed to a random sample of 1,200 Oncology Nursing Society (ONS) members and 75 members of the ONS-Cancer Genetics Special Interest Group; 656 (51%) of those eligible responded. After exclusions, we analyzed 573 responses. Most respondents were Caucasian, female, and worked in hospital or outpatient settings. Half were staff nurses and 8% specialized in cancer genetics. Respondents with higher levels of nursing education or with continuing education in cancer genetics, who worked in positions other than staff nurses, and whose primary practice area was cancer genetics had significantly higher mean scores overall on questions measuring knowledge of cancer genetics and related areas. Higher perceived educational needs to improve knowledge or practice related to cancer genetics at basic, intermediate or advanced levels were associated with all or some of the following variables: lower education; hospital/ outpatient or managed care/private practice settings; lack of continuing education in cancer genetics, and positions other than advanced practice nurses. Although nearly half of the respondents had received patient inquiries regarding cancer genetics, only 35% were aware of referral resources and 26% had made such referrals. These findings may be used to develop targeted educational approaches that prepare oncology nurses to incorporate cancer genetics into any level of practice.

Intention to learn results of genetic testing for hereditary colon cancer

INTRODUCTION

This report investigates the correlates of intention to find out genetic test results in colorectal cancer patients undergoing genetic counseling and testing for hereditary nonpolyposis colon cancer. Specifically, we investigated whether intention to learn genetic test results was associated with sociodemographic factors, medical history, psychosocial factors, attitudes, beliefs, and decisional considerations related to genetic testing.

MATERIALS AND METHODS

Among 342 colorectal cancer patients who went through an informed consent process and gave blood for genetic testing and who were eligible for a psychosocial questionnaire study, 269 cases completed a baseline interview. Patients were contacted in person during a routine clinic visit or by letter and follow-up telephone call and were interviewed either in person or by telephone.

RESULTS

In univariate analysis, intention to learn test results was positively associated with income, quality of life, a belief that being tested will help family members prevent cancer, being worried about carrying an altered gene, and a belief that one has the ability to cope with test results. It was negatively associated with a belief that genetic counseling is too much trouble relative to the benefits. Intention also was positively associated with scales measuring the pros of learning test results and the pros of informing relatives about test results; it was negatively associated with the cons of learning test results. In multivariable analysis, the belief that testing would help family members prevent cancer, being worried about carrying an altered gene, and the pros of learning test results remained statistically associated with intention when other variables were included in the model.

CONCLUSIONS

Our findings showed that the positive aspects of genetic testing were more strongly associated with intention than were the negative aspects. They also showed that persons who stated an intention to learn their genetic test results were more likely than persons who did not to affirm both the benefits and the importance of such testing. These results are consistent with the literature on psychosocial aspects of genetic testing for breast cancer.

Correlates of psychologic distress in colorectal cancer patients undergoing genetic testing for hereditary colon cancer

In this article the authors describe the demographic and psychosocial correlates of 2 measures of psychologic distress among 200 colorectal cancer patients undergoing genetic testing for hereditary nonpolyposis colon cancer. The prevalence of symptoms of depression on the Center for Epidemiologic Studies Depression (CES-D) Scale was 24%. In multivariate analysis, female sex, less formal education, fewer sources of social contacts, and less satisfaction with them were associated with high scores on the CES-D Scale. Characteristics associated with high scores on the State-Trait Anxiety Inventory were younger age, less formal education, non-White race, local-regional stage of disease, fewer social contacts, and less satisfaction with them. Information on psychosocial correlates of psychologic distress may prove useful in guiding genetic counseling sessions, in identifying subgroups that need more intensive follow-up, and in developing interventions to facilitate adjustment to genetic test results.

Correlates of psychologic distress in colorectal cancer patients undergoing genetic testing for hereditary colon cancer

In this article the authors describe the demographic and psychosocial correlates of 2 measures of psychologic distress among 200 colorectal cancer patients undergoing genetic testing for hereditary nonpolyposis colon cancer. The prevalence of symptoms of depression on the Center for Epidemiologic Studies Depression (CES-D) Scale was 24%. In multivariate analysis, female sex, less formal education, fewer sources of social contacts, and less satisfaction with them were associated with high scores on the CES-D Scale. Characteristics associated with high scores on the State-Trait Anxiety Inventory were younger age, less formal education, non-White race, local-regional stage of disease, fewer social contacts, and less satisfaction with them. Information on psychosocial correlates of psychologic distress may prove useful in guiding genetic counseling sessions, in identifying subgroups that need more intensive follow-up, and in developing interventions to facilitate adjustment to genetic test results.