Incisional infiltration versus transversus abdominis plane block of liposomal bupivacaine after midline vertical laparotomy for suspected gynecologic malignancy: a pilot study

Background

To evaluate whether incisional infiltration of liposomal bupivacaine would decrease opioid requirement and pain scores after midline vertical laparotomy for suspected or known gynecologic malignancy compared with transversus abdominis plane (TAP) block with liposomal bupivacaine.

Methods

A prospective, single blind randomized controlled trial compared incisional infiltration of liposomal bupivacaine plus 0.5% bupivacaine versus TAP block with liposomal bupivacaine plus 0.5% bupivacaine. In the incisional infiltration group, patients received 266 mg free base liposomal bupivacaine with 150 mg bupivacaine hydrochloride. In the TAP block group, 266 mg free base bupivacaine with 150 mg bupivacaine hydrochloride was administered bilaterally. The primary outcome was total opioid use during the first 48-hour postoperative period. Secondary outcomes included pain scores at rest and with exertion at 2, 6, 12, 24 and 48 h after surgery.

Results

Forty three patients were evaluated. After interim analysis, a three-fold higher sample size than originally calculated was required to detect a statistically significant difference. There was no clinical difference between the two arms in mean opioid requirement (morphine milligram equivalents) for the first 48 h after surgery (59.9 vs. 80.8, p = 0.13). There were no differences in pain scores at rest or with exertion between the two groups at pre-specified time intervals.

Conclusion

In this pilot study, incisional infiltration of liposomal bupivacaine and TAP block with liposomal bupivacaine demonstrated clinically similar opioid requirement after gynecologic laparotomy for suspected or known gynecologic cancer. Given the underpowered study, these findings cannot support the superiority of either modality after open gynecologic surgery.

Comparison of the treatment efficacies of HIFU, HIFU combined with GnRH-a, and HIFU combined with GnRH-a and LNG-IUS for adenomyosis: A systematic review and meta-analysis

To compare the treatment efficacies of high-intensity focused ultrasound (HIFU), HIFU combined with gonadotrophin-releasing hormone agonist (GnRH-a), and HIFU combined with GnRH-a and levonorgestrel-releasing intrauterine system (LNG-IUS) for adenomyosis. We conducted a literature search in SCIENCE DIRECT, COCHRANE LIBRARY, WILLEY ONLINE LIBRARY, PUBMED, and TAYLOR FRANCIS. A total of 471 articles identified, 12 were included in a systematic review, and 11 of them deemed quantitively eligible included in the meta-analysis. The efficacies of the three treatment regimens were assessed using the dysmenorrhea and menstrual scores at 3, 6, 12, 24 months. Of the three regimens, HIFU combined with GnRH-a and LNG-IUS provides the best outcome. On dysmenorrhea score at 6 months there was significantly different higher heterogeneity with P < 0.00001 (I² = 100% WMD 21.44 [6.34, 36.53]) with statistical significance P = 0.005. At 12 months there was significantly different higher heterogeneity P < 0.00001 (I² = 100% WMD 23.47 [6.00, 40.94]) with statistically significant P < 0.008. At 24 months there was significantly different higher heterogeneity P < 0.0005 (I² = 92% WMD 6.05 [4.81, 7.30]) with statistical significance P < 0.00001. HIFU combined with GnRH-a and LNG-IUS on menstrual score at 3 months was significantly different higher heterogeneity with P < 0.00001 (I² = 100% WMD 56.23 [16.01, 96.45]) with statistical significance P = 0.006. At 6 months there was significantly different higher heterogeneity P < 0.00001 (I² = 99% WMD 93.86 [64.15, 123.57]) with statistical significance P < 0.00001. At 12 months there was significantly different higher heterogeneity P < 0.00001 (I² = 99% WMD 97.13 [67.81, 126.46]) with statistical significance P < 0.00001 compared to treatments with only HIFU and HIFU combined with GnRH-a. HIFU combined with GnRH-a and LNG-IUS treatment is more effective than only HIFU monotherapy and HIFU combined with GnRH-a.

Management and Care of Patients With Invasive Cervical Cancer: ASCO Resource-Stratified Guideline Rapid Recommendation Update

ASCO Rapid Recommendations Updates highlight revisions to select ASCO guideline recommendations as a response to the emergence of new and practice-changing data. The rapid updates are supported by an evidence review and follow the guideline development processes outlined in the ASCO Guideline Methodology Manual. The goal of these articles is to disseminate updated recommendations, in a timely manner, to better inform health practitioners and the public on the best available cancer care options.

Comparison of magnetic resonance-guided high-intensity focused ultrasound with uterine artery embolization for the treatment of uterine myoma: A systematic literature review and meta-analysis

OBJECTIVE

This study aimed to compare the outcomes of magnetic resonance-guided (MR-g) high-intensity focused ultrasound (HIFU) with uterine artery embolization (UAE) for the treatment of uterine myoma.

MATERIALS AND METHODS

A systematic literature review and meta-analysis was conducted using database searches of Medline, Cochrane, EMBASE, and Google Scholar. Articles were searched through March 25, 2020. Outcomes of interest were Symptom Severity Score (SSS), Health-related Quality of Life (HRQoL), re-intervention rate, and rate of adverse reactions in patients with uterine myoma.

RESULTS

Four studies were included with a total of 207 patients with uterine myomas who received MR-g HIFU and 201 who received UAE. UAE was associated with a greater reduction in SSS, improved HRQoL, and a significantly lower re-intervention rate compared with MR-g HIFU in 3 of 4 included studies. No significant differences were found in the incidence and severity of adverse events between treatment arms in one study, but differences were observed in the percentage of adverse reactions in another.

CONCLUSION

Published evidence suggests that the efficacy of MR-g HIFU may not be superior to that of UAE in the treatment of uterine myoma.

Assessment of Adult Women With Ovarian Masses and Treatment of Epithelial Ovarian Cancer: ASCO Resource-Stratified Guideline

PURPOSE

To provide expert guidance to clinicians and policymakers in three resource-constrained settings on diagnosis and staging of adult women with ovarian masses and treatment of patients with epithelial ovarian (including fallopian tube and primary peritoneal) cancer.

METHODS

A multidisciplinary, multinational ASCO Expert Panel reviewed existing guidelines, conducted a modified ADAPTE process, and conducted a formal consensus process with additional experts.

RESULTS

Existing sets of guidelines from eight guideline developers were found and reviewed for resource-constrained settings; adapted recommendations from nine guidelines form the evidence base, informing two rounds of formal consensus; and all recommendations received ≥ 75% agreement.

RECOMMENDATIONS

Evaluation of adult symptomatic women in all settings includes symptom assessment, family history, and ultrasound and cancer antigen 125 serum tumor marker levels where feasible. In limited and enhanced settings, additional imaging may be requested. Diagnosis, staging, and/or treatment involves surgery. Presurgical workup of every suspected ovarian cancer requires a metastatic workup. Only trained clinicians with logistical support should perform surgical staging; treatment requires histologic confirmation; surgical goal is staging disease and performing complete cytoreduction to no gross residual disease. In first-line therapy, platinum-based chemotherapy is recommended; in advanced stages, patients may receive neoadjuvant chemotherapy. After neoadjuvant chemotherapy, all patients should be evaluated for interval debulking surgery. Targeted therapy is not recommended in basic or limited settings. Specialized interventions are resource-dependent, for example, laparoscopy, fertility-sparing surgery, genetic testing, and targeted therapy. Multidisciplinary cancer care and palliative care should be offered.Additional information can be found at www.asco.org/resource-stratified-guidelines. It is ASCO's view that health care providers and health care system decision makers should be guided by the recommendations for the highest stratum of resources available. The guideline is intended to complement but not replace local guidelines.

Integrated genomic and functional analysis of patient-derived sarcoma cell lines validates their use for candidate treatment discovery including knockdown of a novel BCOR fusion gene

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Background: Malignant peripheral nerve sheath tumors (MPNST) are rare, biologically-aggressive soft tissue sarcomas of neural origin, characterized by high risk of recurrence, metastases, treatment resistance and lethality. Preclinical models accurately reflecting underlying genetics are needed for exploring the tumor’s biology and developing novel therapeutic approaches. Using genomic, biochemical and bioinformatic approaches we generated and deeply characterized a patient-derived MPNST cell-line model (PDCL) and functionally validated identified therapeutic targets including a novel BCOR fusion gene. Methods: Under IRB consent, two geographically distinct metastatic tumor samples were obtained from a right peritoneal nodule (PN) and the pelvis (P) of a 63-year-old woman, with recurrent uterine MPNST to generate PDCL. Whole exome (WES) and RNA sequencing was performed on all samples. Data and bioinformatic analysis was performed using the QIAGEN software suite (CLC Genomic Workbench, Ingenuity Variant and Pathway Analysis, OmicSoft-ArrayStudio). Results: To define the degree of shared genomic diversity, WES and RNAseq of tumors and PDCL was performed. WES of metastatic samples identified both shared (n = 39) and novel (98 and 116, respectively) cancer driver variants, which were also present in the paired PDCL (38% and 39%, respectively). Furthermore, somatic copy number alterations (SCNAs) were also shared between tissue and paired PDCL. These SCNAs are present in the MPNST TCGA dataset suggesting broad biologic significance. Finally, a novel and expressed BCOR-CREBRF fusion was present in all samples. With the potential to identify and validate candidate therapies, bioinformatic analysis was used to identify shared canonical signaling pathways (Ephrin receptor signaling) and upstream regulators (HBEGF, VEGFA, and ERBB2) between tumors and PDCL. Based upon this analysis, the inhibitory effects of a targeted list of candidate drugs was performed: Dasatinib, Pazopanib, PD153035, and Lapatinib all selectively resulted in tumor cell death. Moreover, siRNA-mediated BCOR-CREBRF knockdown significantly inhibited PDCL growth. Conclusions: We demonstrate that MPNST PDCL capture the genomic diversity inherent in their founder tumor tissues and potentially other MPNST. Moreover, using a bioinformatic approach for therapeutic discovery, demonstrate the use of these PDCL for testing treatment candidates for possible use in MPNST patients.

Efforts towards erasing borders in gynecologic cancer?

•Cervical cancer is the second most common cancer among women in LMIC.•Major efforts to improve research in gynecologic cancer in LMIC are needed.•GOR provides a platform featuring research and review of cancer care in LMIC.

Cervical cancer control in HIV-infected women: Past, present and future

Since the initial recognition of acquired immunodeficiency syndrome (AIDS) in 1981, an increased burden of cervical cancer was identified among human immunodeficiency virus (HIV)-positive women. Introduction of antiretroviral therapy (ART) decreased risks of opportunistic infections and improved overall survival. HIV-infected women are living longer. Introduction of the human papillomavirus (HPV) vaccine, cervical cancer screening and early diagnosis provide opportunities to reduce cervical cancer associated mortality. In line with 2030 Sustainable Development Goals to reduce mortality from non-communicable diseases, increased efforts need to focus on high burden countries within sub-Saharan Africa (SSA). Despite limitations of resources in SSA, opportunities exist to improve cancer control. This article reviews advancements in cervical cancer control in HIV-positive women.

Cervical cancer: A global health crisis

Cervical cancer is the fourth most common malignancy diagnosed in women worldwide. Nearly all cases of cervical cancer result from infection with the human papillomavirus, and the prevention of cervical cancer includes screening and vaccination. Primary treatment options for patients with cervical cancer may include surgery or a concurrent chemoradiotherapy regimen consisting of cisplatin-based chemotherapy with external beam radiotherapy and brachytherapy. Cervical cancer causes more than one quarter of a million deaths per year as a result of grossly deficient treatments in many developing countries. This warrants a concerted global effort to counter the shocking loss of life and suffering that largely goes unreported. This article provides a review of the biology, prevention, and treatment of cervical cancer, and discusses the global cervical cancer crisis and efforts to improve the prevention and treatment of the disease in underdeveloped countries. Cancer 2017;123:2404-12. © 2017 American Cancer Society.

Laparoscopic surgery for gynecologic cancer in low- and middle-income countries (LMICs): An area of need

Over 90% of people living in low- and middle-income countries (LMICs) do not have access to surgical care. In the absence of appropriate surgical care, there is high morbidity and mortality from surgically curable diseases, such as cervical cancer. Laparoscopic surgery for gynecologic cancer in LMICs is extremely limited. The benefits of laparoscopy over open surgery are even more pronounced in LMICs than in resource-rich countries. Barriers to implementation of laparoscopic surgery in LMICs should be identified and addressed in order to improve global cancer care and the lives of women worldwide.

Management and Care of Women With Invasive Cervical Cancer: American Society of Clinical Oncology Resource-Stratified Clinical Practice Guideline

Purpose

To provide evidence-based, resource-stratified global recommendations to clinicians and policymakers on the management and palliative care of women diagnosed with invasive cervical cancer.

Methods

ASCO convened a multidisciplinary, multinational panel of cancer control, medical and radiation oncology, health economic, obstetric and gynecologic, and palliative care experts to produce recommendations reflecting resource-tiered settings. A systematic review of literature from 1966 to 2015 failed to yield sufficiently strong quality evidence to support basic- and limited-resource setting recommendations; a formal consensus-based process was used to develop recommendations. A modified ADAPTE process was also used to adapt recommendations from existing guidelines.

Results

Five existing sets of guidelines were identified and reviewed, and adapted recommendations form the evidence base. Eight systematic reviews, along with cost-effectiveness analyses, provided indirect evidence to inform the consensus process, which resulted in agreement of 75% or greater.

Recommendations

Clinicians and planners should strive to provide access to the most effective evidence-based antitumor and palliative care interventions. If a woman cannot access these within her own or neighboring country or region, she may need to be treated with lower-tier modalities, depending on capacity and resources for surgery, chemotherapy, radiation therapy, and supportive and palliative care. For women with early-stage cervical cancer in basic settings, cone biopsy or extrafascial hysterectomy may be performed. Fertility-sparing procedures or modified radical or radical hysterectomy may be additional options in nonbasic settings. Combinations of surgery, chemotherapy, and radiation therapy (including brachytherapy) should be used for women with stage IB to IVA disease, depending on available resources. Pain control is a vital component of palliative care. Additional information is available at www.asco.org/rs-cervical-cancer-treatment-guideline and www.asco.org/guidelineswiki. It is the view of ASCO that health care providers and health care system decision makers should be guided by the recommendations for the highest stratum of resources available. The guideline is intended to complement but not replace local guidelines.

American Society of Clinical Oncology Statement: Human Papillomavirus Vaccination for Cancer Prevention

American Society of Clinical Oncology (ASCO), the leading medical professional oncology society, is committed to lessening the burden of cancer and as such will promote underused interventions that have the potential to save millions of lives through cancer prevention. As the main providers of cancer care worldwide, our patients, their families, and our communities look to us for guidance regarding all things cancer related, including cancer prevention. Through this statement and accompanying recommendations, ASCO hopes to increase awareness of the tremendous global impact of human papillomavirus (HPV) -caused cancers, refocus the discussion of HPV vaccination on its likely ability to prevent millions of cancer deaths, and increase HPV vaccination uptake via greater involvement of oncology professionals in ensuring accurate public discourse about HPV vaccination and calling for the implementation of concrete strategies to address barriers to vaccine access and acceptance.

Omega-3 dietary Fatty Acid status of healthy older adults in Tasmania, Australia: an observational study

OBJECTIVES

To determine the dietary and supplement intake of omega-3 (n-3) polyunsaturated fatty acids (PUFA) of older Tasmanian adults; their plasma n-3 PUFA status and the relationship between n-3 PUFA intake and plasma status.

DESIGN

Cross-sectional study.

SETTING

Launceston and surrounding regions, Tasmania, Australia.

PARTICIPANTS

Seventy-three community-dwelling older adults: 23 men aged 70 ± 6.1 years and 50 women aged 70 ± 6.7 years.

MEASUREMENTS

A validated, semi-quantitative food frequency questionnaire estimated dietary PUFA intake. The plasma phospholipid fraction of venous blood samples was analysed for fatty acid content. Anthropometric data was recorded.

RESULTS

Thirty-five participants (48%) regularly ingested a fish oil supplement. Their plasma n-3 PUFA profile contained significantly more eicosapentaenoic acid (EPA) (odds ratio 3.14; 95% CI 1.37% to 7.30%; p<0.05) and docosahexaenoic acid (DHA) (odds ratio 2.64; 95% CI 1.16% to 6.01%; p<0.05) than non-supplement users. Fish and meat were the main dietary sources of n-3 PUFAs. Participants most commonly consumed fish 3-4 times per week. Significant associations of dietary α-linolenic acid (ALA), EPA, docosapentaenoic acid (DPA) and DHA with plasma n-3 PUFAs were noted but not always between dietary and plasma counterparts.

CONCLUSION

Without the use of fish oil supplements, most study participants were unable to meet the recommended daily intake of 0.5g EPA and DHA combined; however, the plasma n-3 PUFA profile of non-supplement-users was still robust compared to other Australian and overseas studies.

Comparison of robotic-assisted and conventional laparoscopy in the management of adnexal masses

STUDY OBJECTIVE

To compare the outcome of robotic-assisted laparoscopy vs conventional laparoscopy in the management of ovarian masses.

DESIGN

Retrospective cohort (Canadian Task Force classification II-3).

SETTING

Academic medical centre in the northeast United States.

PATIENTS

Retrospective medical record review of 71 consecutive patients with presumed benign ovarian masses.

INTERVENTION

Robotic-assisted laparoscopy in 30 patients with presumed benign ovarian masses was compared with conventional laparoscopy in 41 patients.

MEASUREMENTS AND MAIN RESULTS

Operative outcomes including operative time, estimated blood loss, length of hospital stay, and complications were recorded. Standard statistical analysis was used to compare the outcomes in the 2 groups. Mean (SD) operative time in the robotic group was 1.95 (0.63) hours, which was significantly longer than in the conventional laparoscopic group, 1.28 (0.83) hours (p = .04). Estimated blood loss in the robotic group was 74.52 (56.23) mL, which was not significantly different from that in the conventional laparoscopic group, 55.97 (49.18) mL. There were no significant differences in length of hospital stay between the robotic and conventional laparoscopic groups: 1.20 (0.78) days and 1.48 (0.63). Conversion to laparotomy was not necessary in either group of patients. Intraoperative and postoperative complications were similar between the 2 groups.

CONCLUSION

Robotic-assisted laparoscopy is a safe and efficient technique for management of various types of ovarian masses. However, conventional laparoscopy is preferred for management of ovarian masses because of shorter operative time. Prospective studies are needed to evaluate the outcomes of robotic-assisted laparoscopic management of benign and malignant ovarian neoplasms.

Quality of life and sexual function of patients following radical hysterectomy and vaginal extension

INTRODUCTION

Radical hysterectomy (RH) has negative consequences on sexual function due to a shortened vagina, vaginal dryness, and dyspareunia. Peritoneovaginoplasty aims to extend vagina by vesical peritoneum and anterior rectal wall to improve postoperative sexual function.

AIM

The aim of this study was to investigate whether vaginal extension can improve sexual function and quality of life and the problem of sexual dysfunction in early-stage cervical cancer survivors (CCSs) in China.

METHODS

Case-control and questionnaire-based methods were employed. Thirty-one patients who had undergone vaginal extension following RH and 28 patients with matching factors after RH alone were enrolled in the study.

MAIN OUTCOME MEASURES

Both groups were assessed retrospectively by questionnaires at least 6 months after treatment. The European Organization for Research and Treatment of Cancer Quality-of-Life questionnaire cervical cancer module and the Sexual Function Vaginal Changes Questionnaire are validated measurements for disease- and treatment-specific issues.

RESULTS

Vaginal length was 10.03 ± 1.26 cm and 5.92 ± 1.05 cm in study and control group, respectively (P < 0.05). In the study group, 67.7% patients and 64.3% of control group resumed sexual activity at the time of interview, averaging 6 months between treatment and sexual activity. While difficulty emptying bladder, incomplete emptying, and constipation were the most commonly reported symptoms, no significant difference was observed regarding pelvic floor symptoms. Reduced vagina size and shortened vagina was significantly more prominent in the control group, whereas both group presented with hypoactive sexual desire (88.1%), orgasm dysfunction (71.8%), and low enjoyment or relaxation after sex (51.3%).

CONCLUSION

Shortened vagina was significantly less reported in study group, while no difference was observed in other sex-related dimensions. Vaginal extension does not worsen pelvic floor symptoms. Sexual rehabilitation interventions are of significance and should be paid more attention to the CCSs in China.

Pelvic irradiation versus pelvic irradiation with concurrent chemotherapy followed by extrafascial hysterectomy in the treatment of locally advanced cervical cancer in Honduras

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Background: Because of the lack of brachytherapy in Honduras, patients with locally advanced cervical cancer underwent extrafascial hysterectomy after upfront pelvic irradiation or pelvic irradiation with concurrent chemotherapy. Methods: We compared the effect of pelvic radiotherapy with that of pelvic radiation and concurrent chemotherapy with cisplatin in women with advanced cervical cancer. Between 2008 and 2011, 165 women with advanced cervical cancer confined to the pelvis (stages IB2 through IIIB) received either 70 Gy of radiation to the pelvis alone or with concurrent weekly cisplatin. Patients underwent subsequently extrafascial hysterectomy six weeks after completion of radiation therapy. Results: Of the 165 eligible patients, 90 (54.5%) patients received only pelvic radiation therapy, and 75 (45.5%) patients received pelvic radiation and chemotherapy. Squamous cell carcinoma was identified in 135 (82%) cases and adenocarcinoma in 30 (18%) cases. On the final hysterectomy specimen, 69 (77.8%) patients who received pelvic radiation had a complete clinical response with no residual diseases; there were 40 (53.3%) patients who received pelvic radiation and chemotherapy achieved a complete response (p<0.001). In the group of patients that were treated with pelvic radiation and chemotherapy, only 25 out of 75 (33.3%) patients received the required cisplatin on schedule. The complete clinical response rate of the 25 patients who received the complete course of pelvic radiation and chemotherapy was 80%. Conclusions: Treatment of locally advanced cervical cancer in low-resource settings is met with challenges including the lack of brachytherapy, and unpredictable availability of chemotherapy. Only 33% of patients that were treated with the intention of concurrent chemo-radiation were able to receive cisplatin on schedule. This resulted in a significantly lower response in the patients who were treated with pelvic radiation and chemotherapy. In settings where the availability of chemotherapy is not always available, primary pelvic radiation for advanced cervical cancer resulted in a better treatment response.

Sulforaphane induces growth arrest and apoptosis in human ovarian cancer cells

OBJECTIVES

Isothiocyanates (ITC) from broccoli and other cruciferous vegetables have long been shown to have chemopreventive properties, as demonstrated in cancer models in rodents. Sulforaphane (SFN) is a major ITC present in broccoli. We examined the effects of SFN on the growth of the OVCAR-3 and SKOV-3 ovarian carcinoma cell lines.

METHODS

Cell cycle phase determination was performed using a Coulter flow cytometer. DNA strand breaks in apoptotic cells were measured by terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end-labelling (TUNEL).

RESULTS

There was a concentration dependent decrease in cell density. Approximately 50% decrease was observed after 48 h of incubation with SFN (2 μM). Analysis of cell cycle phase progression revealed a decrease in the cell populations in S and G2M phases, with an increase of G1 cell population, indicating a G1 cell cycle arrest. The degree of decrease in the replicating population was concentration and time dependent. Incubation of OVCAR-3 cells in cultures with concentrations of 2, 10 and 50 μM of SFN showed 6, 8 and 17% apoptosis, respectively. In addition, when OVCAR-3 cells were exposed to SFN for various time periods (1, 2 or 3 days), the percentage of cells undergoing apoptosis was directly proportional to the incubation period. In this regard, while 18% of the cells underwent apoptosis after 2 days, 42% of the cells showed apoptosis after 3 days of incubation.

CONCLUSIONS

These results clearly demonstrated an effect of SFN in inducing growth arrest and apoptosis in ovarian carcinoma cell lines.

Correlation of the fatty acid composition and fluid property of the cholesteryl esters in the serum of Nigerian children with sickle cell disease and healthy controls

In a previous study conducted in Nigeria, we found that children with sickle cell disease (SCD) had exceedingly low total serum cholesterol levels (mean=100-102mg/dl). The fact that significant reductions in the levels of certain polyunsaturated fatty acids (PUFA) have been documented in the serum phospholipids of these same SCD subjects led us to inquire as to the fatty acid composition of the cholesteryl esters (CE) in their serum. Lecithin:cholesterol acyl transferase (LCAT), the enzyme in blood that catalyzes the reaction in which tissue cholesterol is acylated prior to its removal from cell membranes, is relatively specific for certain PUFA. CE in blood serum from 43 male and 42 female children with SCD, ages 4-18 years, and equal numbers of age- and gender-matched controls were analyzed for their fatty acid composition. Relative to the non-SCD controls, the CE of the SCD subjects contained 9% less linoleic acid, 16% less arachidonic acid, 40% less alpha-linolenic acid, 50% less eicosapentaenoic acid, and 36% less docosahexaenoic acid, but 15% more palmitic acid and 10% more oleic acid. Overall, the acyl chains of the CE of the SCD subjects were less fluid than those of the controls, as determined by comparison of their mean melting points (MMP) and double bond indices (DBI). MMP and DBI were both estimated from the individual constituent fatty acids comprising the CE acyl chains. The strongest correlations between MMP and fatty acid mole percent were seen with palmitic acid and linoleic acid. These results show that the fatty acid composition of the serum CE of children with SCD is abnormal relative to controls who do not have this hematologic disorder. We speculate that suboptimal fatty acid nutrition in Nigerian children with SCD compromises their ability to remove cholesterol from their tissues due to preference of the LCAT enzyme for PUFA, thereby accounting, in part at least, for the low total serum cholesterol levels one finds in children with SCD.

Protective effect of HO-1 against oxidative stress in human hepatoma cell line (HepG2) is independent of telomerase enzyme activity

Heme oxygenase-1 (HO-1) is a stress response protein and its induction is associated with protection against oxidative stress. Cell survival during exposure to environmental stresses is associated with elevation of HO-1. Telomerase plays an important role in cell proliferation and immortalization. Our objective was to determine whether the adaptive cellular response to survive exposure to environmental stresses is dependent on expression of HO-1 and telomerase activity in hepatoma cell line (HepG2). Exposure of HepG2 to oxidants, H(2)O(2) (100 microM), as well as HO-1 inducers, heme (10 microM) and stannic chloride (SnCl(2)) (10 microM), resulted in an increased HO-1 mRNA, protein and total HO activity. On the other hand, HO activity was inhibited by addition of stannic mesoporphyrin (SnMP) (10 microM). These effects were brought about without altering endogenous HO-2 protein levels. Telomerase activity was not affected by oxidants, inducers of HO-1 or inhibitors of HO activity. Similarly, the catalytic subunit of telomerase enzyme human telomerase reverse transcriptase (hTERT), which is considered as the major regulator of telomerase activity, was not affected by oxidants, heme and H(2)O(2), or downregulation of HO gene activity by SnMP. This study demonstrates, for the first time, that induction of HO-1 gene mediates protection against oxidants and increases cell survival by a mechanism independent of telomerase enzyme activity. Suppression of HO activity by SnMP decreased cell resistance to oxidant stressors without altering telomerase activity.

Expression of fungal desaturase genes in cultured mammalian cells

Long-chain polyunsaturated fatty acids (LC-PUFA) are important components of cellular structure and function. Most of LC-PUFA are derived from linoleic acid and alpha-linolenic acid. In plants and fungi, these two acids can be synthesized from oleic acid via the action of two enzymes, delta12 and delta15-desaturases. Due to lack of these enzymatic activities and the ability to synthesize these two essential fatty acids, animals must obtain them from the diet. In this report, we demonstrated the expression of a fungal delta12-desaturase gene in mouse L cells incubated in serum-free medium. The results showed a significant increase in the amount of linoleic acid with a concomitant decrease of oleic acid in cellular lipids. Most of the newly formed linoleic acid was incorporated into cellular phospholipids, particularly phosphatidylcholine. The increase of linoleic acid provided the substrate for the endogenous synthesis of (n-6) LC-PUFA, such as eicosadienoic acid (EDA), dihomo-gamma-linoleic acid (DGLA) and arachidonic acid (AA). Prolonged incubation further increased the levels of linoleic acid derived from oleic acid by the action of delta12-desaturase, and the levels of 20:2n-6 produced from linoleic acid by the action of the endogenous elongase. However, prolonged incubation suppressed significantly the formation of DGLA and AA. In a separate study, a fungal delta6-desaturase gene has also been expressed in the mouse L cells incubated in serum-containing medium. The result shows a significant increase in levels of 20:3n-6 and 20:4n-6. These findings demonstrate that through genetic modification, it is possible to (1) generate cell lines which no longer require dietary 'essential' fatty acids and (2) alter the endogenous fatty acid metabolism to enhance the production of LC-PUFA and their derivatives.

Inhibitory effect of conjugated linoleic acid on linoleic acid elongation in transformed yeast with human elongase

Conjugated linoleic acid (CLA; 18:2) refers to a group of positional and geometric isomers derived from linoleic acid (LA; delta9,12-18:2). Using a growing baker's yeast (Saccharomyces cerevisiae) transformed with human elongase gene, we examined the inhibitory effect of CLA at various concentrations (10, 25, 50, and 100 microM) on elongation of LA (25 microM) to eicosadienoic acid (EDA; delta11,14-20:2). Among four available individual CLA isomers, only c9,t11- and t10,c12-isomers inhibited elongation of LA to EDA. The extent of inhibition (ranging from 20 to 60%) was related to the concentration of CLA added to the medium. In the meantime, only these two isomers, when added at 50 microM to the media, were elongated to conjugated FDA (c11,t13- and t12,c14-20:2) by the same recombinant elongase at the rate of 28 and 24%, respectively. The inhibitory effect of CLA on LA elongation is possibly due to competition between CLA isomers and LA for the recombinant elongase. Thus, results from this study and a previous study suggest that the biological effect of CLA is exerted through its inhibitory effect on delta6-desaturation as well as elongation of LA which results in a decrease in long-chain n-6 fatty acids and consequently the eicosanoid synthesis.

Fatty acid composition of the milk lipids of Nepalese women: correlation between fatty acid composition of serum phospholipids and melting point

Milk was collected from 36 Nepalese women, 15 to 32 years of age, in order to investigate relationships between the proportions of intermediate chain-length (C10-C14) fatty acids and critical n-3 and n-6 polyunsaturated fatty acids in the milk lipids they were producing. Serum was also obtained from these lactating women and the fatty acid composition of their serum phospholipid fraction was determined and compared with that of the corresponding milk lipid fraction. Compared to women in technologically advanced parts of the world, the serum phospholipids of the Nepalese women contained nutritionally adequate proportions of linoleic acid (LA) (16.8%), alpha-linolenic acid (ALA) (0.53%), arachidonic acid (AA) (5.69%), and docosahexaenoic acid (DHA) (1.42%). However, although the milk lipids contained adequate proportions of ALA (1.81%), AA (0.43%), and DHA (0.23%), the lipids contained low to moderate percentages of LA (mean, 9.05%). Positive correlations were observed between the proportions of AA (P=0.001, r=0.50) and ALA (P=0.03, r=0.36) in the serum phospholipids and milk lipids of the women. As the proportion of C10-Cl4 fatty acids in the milk lipids increased from 10% to 40%, there was preferential retention of three critical n-3 and n-6 fatty acids (ALA, AA, and DHA) at the expense of two relatively abundant nonessential fatty acids, namely stearic acid and oleic acid. In addition, using fatty acid melting point data and the mol fraction of the 9 most abundant fatty acids in the milk, we estimated the mean melting point (MMP) of the milk lipids of the Nepalese women. The MMPs ranged from 29.3 to 40.5 degrees C (median, 35.5 degrees C). These results indicate that: 1) the levels of AA and ALA in the blood of lactating mothers influence the levels of these fatty acids in the milk they produce; 2) when the mammary gland produces a milk that is rich in C10-Cl4 fatty acids, it somehow regulates triglyceride synthesis in such a way as to ensure that the milk will provide the exclusively breast-fed infant with the amounts of the critical n-3 and n-6 fatty acids it requires for normal growth and development; and 3) the melting point of the milk lipid fraction is determined mainly by the mol % of the intermediate chain-length (C10-C14) fatty acids, oleic acid, linoleic acid, and alpha-linolenic acid.

Effect of conjugated linoleic acid on fungal delta6-desaturase activity in a transformed yeast system

Conjugated linoleic acid (CLA; 18:2), a group of positional and geometric isomers of linoleic acid (LA; 18:2n-6), has been shown to modulate immune function through its effect on eicosanoid synthesis. This effect has been attributed to a reduced production of n-6 polyunsaturated fatty acid (PUFA), the precursor of eicosanoids. Since delta6-desaturase is the rate-limiting enzyme of the n-6 PUFA production, it is our hypothesis that CLA, which has similar chemical structure to LA, interacts directly with delta6-desaturase. A unique and simple model, i.e., baker's yeast (Saccharomyces cerevisiae) transformed with fungal delta6-desaturase gene, previously established, was used to investigate the direct effect of CLA on delta6-desaturase. This model allows LA to be converted to y-linolenic acid (GLA; 18:3n-6) but not GLA to its metabolite(s). No metabolites of CLA were found in the lipids of the yeast transformed with delta6-desaturase. The inability to convert CLA to conjugated GLA was not due to the failure of yeast cells to take up the CLA isomers. CLA mixture and individual isomers significantly inhibited the activity of delta6-desaturase of the transformed yeast in vivo. Even though its uptake by the yeast was low, CLA c9,t11 isomer was found to be the most potent inhibitor of the four isomers tested, owing to its high inhibitory effect on delta6-desaturase. Since CLA did not cause significant changes in the level of delta6-desaturase mRNA, the inhibition of GLA production could not be attributed to suppression of delta6-desaturase gene expression at the transcriptional level.

Fatty acid composition of the milk lipids of Fulani women and the serum phospholipids of their exclusively breast-fed infants

We previously reported that, relative to milk of women elsewhere in the world, the lipid fraction of milk of Fulani women in northern Nigeria contained relatively low proportions of alpha-linolenic acid and docosahexaenoic acid (DHA). This led us to question the essential fatty acid status of Fulani infants and the relation between the proportion of critical n-3 and n-6 fatty acids in the serum phospholipids of the mothers, their milk, and the serum phospholipids of their exclusively breast-fed infants. We were also interested in the effect de novo intermediate chain length-fatty acids (C10-C14) had on the proportions of critical and non-essential fatty acids in milk. Capillary gas-liquid chromatography was used to analyze the fatty acid content of the total milk lipids of 34 Fulani women, as well as the fatty acid content of serum phospholipids of the women and their breast-fed infants during the first 6 months of life. The proportions of critical n-3 and n-6 fatty acids in the milk of the Fulani women were adequate, but the proportions of these same fatty acids were low in their exclusively breast-fed infants. The serum phospholipids of the infants contained 18.8% linoleic acid, 0.13% alpha-linolenic acid, 12.8% arachidonic acid, and 3.40% DHA, whereas, the mean percentages of linoleic, alpha-linolenic, arachidonic and DHA in the serum phospholipids of the Fulani mothers' were 21.4, 0.20, 9.79, and 1.97, respectively. There was a strong positive correlation between fatty acid content of serum phospholipids of Fulani women and the fatty acid content of their milk lipids. As the proportion of C10-C14 fatty acids in the milk lipids increased, the proportions of critical n-3 and n-6 fatty acids in milk remained relatively constant; however, proportions of three non-essential fatty acids decreased dramatically. C10-C14 fatty acids do not appear to displace critical n-3 and n-6 fatty acids in milk.

Modulation of cholesterol concentration in Caco-2 cells by incubation with different n-6 fatty acids

Incorporation of exogenous cholesterol was compared in human adenocarcinoma colon cells (Caco-2) after incubation with 100 microM of either linoleic acid (LA, 18:2n-6), gamma-linolenic acid (GLA, 18:3n-6), arachidonic acid (AA, 20:4n-6) or adrenic acid (or n-6 docosatetraenoic acid, DTA, 22:4n-6). In both cells 7 days after seeding and 14 days after confluency, incubation with LA significantly raised the proportion of 18:2n-6 but not its long-chain metabolites in cellular phospholipid. Incubation with GLA increased the levels of 18:3n-6, 20:3n-6, and 20:4n-6. Incubation with AA increased the levels of 20:4n-6 and 22:4n-6, and incubation with DTA increased the levels of 22:4n-6 as well as its retro-conversion metabolite, 20:4n-6. A subsequent addition of cholesterol (180 microM) to the medium significantly raised the cellular cholesterol level but less so in the cells 7 days after seeding incubated with GLA. The increase in cellular cholesterol level was generally greater in the cells of 7 days after seeding, particularly those incubated with long-chain highly unsaturated n-6 fatty acids, than in those of 14 days after confluency. These findings suggest that the cell growth and the extent of unsaturation in cell membrane phospholipid fatty acids modulate the incorporation of the exogenous cholesterol into the Caco-2 cells.

Nutritional status and intermediate chain-length fatty acids influence the conservation of essential fatty acids in the milk of northern Nigerian women

The milk of 89 women in northern Nigeria was analyzed for the fatty acid composition of the total milk lipids, and assessed for the effect nutritional status has on the conservation of essential and non-essential fatty acids when the proportions of C(10)-C(14)fatty acids are increased. The women were stratified on the basis of their body mass index, and calculations were made to estimate the effects of a 3.3-fold increase in the proportion of C(10)-C(14)fatty acids on the proportion of alpha-linolenic acid, docosahexaenoic acid, linoleic acid and arachidonic in total milk lipids. In the well-nourished group (group III, body mass index >23 kg/m(2)), the critical n-3 and n-6 fatty acids were not conserved, while in poorly nourished women (group I, body mass index <19 kg/m(2)), marked conservation of alpha-linolenic acid, docosahexaenoic acid, arachidonic acid, and palmitic acid was seen. Poor nutritional status of the mother appears to promote selective retention of critical essential and non-essential fatty acids in the milk lipid fraction.

Cloning of a human cDNA encoding a novel enzyme involved in the elongation of long-chain polyunsaturated fatty acids

The Saccharomyces cerevisiae protein ELO2p is involved in the elongation of saturated and monounsaturated fatty acids. Among several sequences with limited identity with the S. cerevisiae ELO2 gene, a consensus cDNA sequence was identified from the LifeSeq(R) database of Incyte Pharmaceuticals, Inc. Human liver cDNA was amplified by PCR using oligonucleotides complementary to the 5' and 3' ends of the putative human cDNA sequence. The resulting full-length sequence, termed HELO1, consisted of 897 bp, which encoded 299 amino acids. However, in contrast with the ELO2 gene, expression of this open reading frame in S. cerevisiae demonstrated that the encoded protein was involved in the elongation of long-chain polyunsaturated fatty acids, as determined by the conversion of gamma-linolenic acid (C(18:3, n-6)) into dihomo-gamma-linolenic acid (C(20:3, n-6)), arachidonic acid (C(20:4, n-6)) into adrenic acid (C(22:4, n-6)), stearidonic acid (C(18:4, n-3)) into eicosatetraenoic acid (C(20:4, n-3)), eicosapentaenoic acid (C(20:5, n-3)) into omega3-docosapentaenoic acid (C(22:5, n-3)) and alpha-linolenic acid (C(18:3, n-3)) into omega3-eicosatrienoic acid (C(20:3, n-3)). The predicted amino acid sequence of the open reading frame had only 29% identity with the yeast ELO2 sequence, contained a single histidine-rich domain and had six transmembrane-spanning regions, as suggested by hydropathy analysis. The tissue expression profile revealed that the HELO1 gene is highly expressed in the adrenal gland and testis. Furthermore, the HELO1 gene is located on chromosome 6, best known for encoding the major histocompatibility complex, which is essential to the human immune response.

cDNA cloning and characterization of human Delta5-desaturase involved in the biosynthesis of arachidonic acid

Two human expressed sequence tag (EST) cDNA sequences with identity with Delta(5)- and Delta(6)-desaturases from a filamentous fungus, Mortierella alpina, were identified from the LifeSeq(R) database of Incyte Pharmaceuticals, Inc. (Palo Alto, CA, U.S.A.). An oligonucleotide complementary to the 3' EST cDNA sequences was used to screen human liver cDNA using rapid amplification of cDNA ends (RACE)-PCR. The amplified DNA fragment had 98% identity with a putative open reading frame (ORF) predicted from a human genomic sequence, and encoded 444 amino acids. Expression of this ORF in mouse fibroblast cells demonstrated that the encoded protein was a Delta(5)-desaturase, as determined by the conversion of dihomo-gamma-linolenic acid (C(20:3,n-6)) into arachidonic acid (C(20:4,n-6)). The human Delta(5)-desaturase contained a predicted N-terminal cytochrome b(5)-like domain, as well as three histidine-rich domains. A tissue expression profile revealed that this gene is highly expressed in fetal liver, fetal brain, adult brain and adrenal gland. A search of the existing databases led to localization of this ORF within a 14 kb interval flanked by the flap endonuclease-1 (FEN1) and vitelliform macular dystrophy (Best's disease; VMD2) loci of chromosome 11q12.

The fatty acid composition of human milk in northern Nigeria

The authors previously reported that the milk of Yoruba women in southwestern Nigeria was deficient in alpha-linolenic acid and contained a high percentage (42%) of medium chain-length fatty acids (MCFA, C10-C14). In the present study, the authors used capillary gas-liquid chromatography to analyze the milk of Hausa women in the northern region of Nigeria. The milk of the Hausa women contained 27% MCFA, 10.6% linoleic acid, 0.41% alpha-linolenic acid, 0.52% arachidonic acid, and 0.32% docosahexaenoic acid. The proportion of alpha-linolenic acid in the serum phospholipids of a subset of exclusively breastfed infants (n = 15; mean age, 6.2 +/- 0.3 months) was below the limit of detection (< 0.03%). While the milk of women in northern Nigeria is adequate with regard to n-3 and n-6 fatty acids, to satisfy the requirements for alpha-linolenic acid, it may be necessary to supplement the infants of these women after the first 6 months of life.

Cytogenetic and molecular characterization of a malignant mixed müllerian tumor of the uterus with a t(8;22)(q24.1;q12)

We report the cytogenetic and molecular findings in a malignant mixed Müllerian tumor of the uterus in a 65-year-old woman. Karyotypic analysis revealed a t(8;22)(q24.1;q12) as the sole abnormality in all 20 cells analyzed. Southern blot analysis of two positional candidate genes, MYC at 8q24, and EWS at 22q12, showed no genomic rearrangement. The finding of the t(8;22) as the only abnormality may be of etiologic significance.

Content of lipid nutrients in the milk of Fulani women

Little is known about the nutrition of the infants of the Fulani, migratory nomads of the western Sahel of Africa. Milk was collected from 18 Fulani women 10 to 30 days postpartum and the fatty acid compositions of the triacylglycerol and phospholipid fractions were determined by capillary gas-liquid chromatography. De novo fatty acids (10:0-14:0) comprised 36.3 +/- 12.7% of fatty acids of the triacylglycerols. Compared to the milk of various populations worldwide, the milk of the Fulani women contained adequate proportions of alpha-linolenic acid (0.50 +/- 0.16%) and arachidonic acid (0.42 +/- 0.22%), but relatively low amounts of linoleic acid (9.95 +/- 2.13%) and docosahexaenoic acid (DHA) (0.15 +/- 0.08%). In addition, the milk of the Fulani women contained adequate concentrations of beta-carotene (1.58 +/- 0.69 micrograms/dl) and vitamin A (42.7 +/- 40.3 micrograms/dl), but very low levels of vitamin E (0.11 +/- 0.10 mg/dl). These data indicate that exclusively breasted infants of Fulani women were receiving relatively low amounts of critical fatty acids and vitamin E.

Abnormal growth induced by expression of HBsAg in the secretion pathway of S. cerevisiae pep4 mutants

The toxicity of HBsAg in the secretion pathway of pep4 strains can be progressively reduced in modified SD media containing lower concentrations of ammonium sulphate. A procedure, combining a reduction of ammonium sulphate concentration in SD media with the disruption of the PEP4 gene of the host strain, was developed to enrich transformants which are not inhibited by HBsAg expressed in the secretion pathway. Abnormal growth of these non-inhibited transformants is characterized by the enlargement of cell morphology, a transition to pseudohyphal-like growth in nitrogen-starved media, an increase in HBsAg particle production, and the enhancement of growth rate in liquid media. This suggests a new approach to overcoming the toxicity of heterologous protein in the yeast secretion pathway.

Alteration of lymphocyte microtubule assembly, cytotoxicity, and activation by the anticancer drug taxol

We studied the effect of the anticancer drug taxol on the cytotoxic mechanism of major histocompatibility complex nonrestricted lymphocytes and their activation with interleukin 2. Unseparated lymphocytes or highly enriched natural killer or T-cells were treated with 0.2-10 micrograms/ml of taxol for various times and tested for cytotoxicity against the K562 cell line and the ovarian cell line, OV-2774. Taxol caused a dose- and time-dependent suppression of lymphocyte cytotoxicity. The most pronounced suppression was noted after treatment with 10 micrograms/ml of taxol for 6 h; a lower but significant decrease in cytotoxicity was observed after treatment with 2 and 5 micrograms/ml of taxol. In addition, taxol inhibited activation of lymphocytes with interleukin 2; however, the cytotoxicity of interleukin 2-preactivated lymphocytes was less sensitive to taxol treatment. Mechanism studies showed that taxol was not directly toxic to lymphocytes and did not alter their ability to form conjugates with target cells. Taxol treatment decreased a rate of kinetics of lysis and lymphocyte recycling ability. The immunofluorescence and electron microscopic analysis showed polymerization of microtubules in taxol-treated lymphocytes. These data demonstrate that taxol impairs lymphocyte cytotoxic function and activation and indicate the role of microtubules in these functions. Clinically, these findings suggest that activation of lymphocytes prior to taxol treatment may increase the therapeutic benefit of this drug.

Oncolytic activity of NK cells against SW-756 squamous cervical carcinoma cell line: role of interferons alpha and gamma and CD54 adhesion molecule in oncolysis

We investigated the sensitivity of a cervical tumor cell line SW-756 to lysis by peripheral blood mononuclear cells (MNC), natural killer (NK) cells, and major histocompatibility complex (MHC)-nonrestricted (MHC-NR) T cells from cervical cancer patients and normal donors. We found that SW-756 was resistant to lysis mediated by naive (unstimulated) MNC and MHC-NR T cells, but sensitive to lysis by naive NK cells. However, the cytotoxic function of MNC could be activated with interleukin-2 (IL-2) and interferon (IFN) alpha or gamma. Although IFNs were effective in enhancement of effector cell cytotoxicity and inhibited proliferation of cervical tumor cells, they also exerted an adverse effect on cytotoxicity; specifically, pretreatment of SW-756 cells with IFNs significantly decreased their susceptibility to lysis by effector cells. Analysis of surface phenotype of SW-756 cells after treatment with IFNs showed up-regulation of expression of HLA class I determinants, the phenomenon that may be responsible for decreased sensitivity of this tumor to MHC-NR NK cells. The studies on the involvement of CD54 adhesion molecule in cytotoxic functions indicated that expression of this molecule on effector cells (but not on target cells) was important for cytotoxicity against SW-756 tumor cells. The therapeutic implication of these studies for patients with cervical cancer is discussed.

Effect of new investigational drug taxol on oncolytic activity and stimulation of human lymphocytes

Taxol is a new antineoplastic agent active in the treatment of drug-refractory ovarian and metastatic breast neoplasms. Extensive investigations have been concerned with the effect of taxol on a variety of tumor cells, but there is virtually no information about its effect on human lymphocytes. Since lymphocytes, especially natural killer (NK) cells, have been recognized to play an important role in the body's defense against tumors, we studied the effect of taxol on the cytotoxicity of naive (unstimulated) peripheral blood mononuclear cells (MNCs) and NK cells as well as on these cells' activation and growth in interleukin-2 (IL-2) cultures. We found that taxol impaired the cytotoxicity of naive MNC and NK cells against the NK-sensitive cell line K-562 and against an ovarian cancer cell line, OV-2774, in a concentration-dependent fashion. The highest impairment was observed after incubation of the effector cells with 10 micrograms/ml taxol. In addition, taxol also interfered with the induction of lymphokine-activated cytotoxicity and with lymphocyte growth in IL-2 cultures. However, IL-2 preactivated NK cells displayed substantial levels of cytotoxicity even after taxol treatment. These findings, which indicate that treatment with taxol should follow rather than precede immunotherapeutic intervention, may be important in planning combined chemo- and immunotherapy strategies for cancer patients.

Non-esterified cholesterol-rich adrenal lipid fractions. Preparation, properties and preferential utilization for cholesterol side-chain cleavage by corticotropin-stimulated adrenal mitochondria

Rat adrenal 105,000 g supernatant contains two lipid moieties, 'lipid-I' and 'lipid-II' which contain non-esterified cholesterol and stimulate cholesterol side-chain cleavage in soluble or mitochondrial enzyme systems. Lipid-I contains relatively large low-density heat-stable particles, whereas lipid-II particles are smaller, more dense and heat-labile. Lipid-I and lipid-II can be separated from clear cytosol by ultracentrifugation and gel filtration respectively. Corticotropin plus cycloheximide treatment increases the non-esterified cholesterol concentrations in the lipid fractions, and stimulatory effects of lipids on cholesterol side-chain cleavage appear to correlate with non-esterified cholesterol concentrations therein. On addition of saturating amounts of cholesterol-rich lipid, pregnenolone synthesis and cholesterol binding to cytochrome P-450 are stimulated more in mitochondria from corticotropin-stimulated adrenals than in mitochondria from control or corticotropin-plus cycloheximide-stimulated adrenals. These results support the contention that the corticotropin-induced increase in mitochondrial cholesterol side-chain cleavage involves an increase in cholesterol utilization as well as an increase in cholesterol availability.