Intermittent fasting induced ketogenesis inhibits mouse epithelial ovarian cancer by promoting antitumor T cell response.

In various cancer models, dietary interventions have been shown to inhibit tumor growth, improve anticancer drug efficacy, and enhance immunity, but no such evidence exists for epithelial ovarian cancer (EOC), the most lethal gynecologic cancer. The anticancer immune responses induced by 16-h intermittent fasting (IF) were studied in mice with EOC. IF consistently reduced metabolic growth factors and cytokines that stimulate tumor growth, creating a tumor-hostile environment. Immune profiling showed that IF dramatically alters anti-cancer immunity by increasing CD4+ and CD8+ cells, Th1 and cytotoxic responses, and metabolic fitness. ß-hydroxy butyrate (BHB), a bioactive metabolite produced by IF, partially imitates its anticancer effects by inducing CD8+ effector function. In a direct comparison, IF outperformed exogenous BHB treatment in survival and anti-tumor immune response, probably due to increased ketogenesis. Thus, IF and one of its metabolic mediators BHB suppress EOC growth and sustain a potent anti-tumor T cell response.

Intermittent Fasting induced ketogenesis inhibits mouse epithelial ovarian tumors by promoting anti-tumor T cell response.

Epithelial Ovarian Cancer (EOC) is the most lethal gynecologic cancer with limited genetic alterations identified that can be therapeutically targeted. In tumor bearing mice, short-term fasting, fasting mimicking diet and calorie restriction enhance the activity of antineoplastic treatment by modulating systemic metabolism and boosting anti-tumor immunity. We tested the outcome of sixteen-hour intermittent fasting (IF) on mouse EOC progression with focus on fasting driven antitumor immune responses. IF resulted in consistent decrease of tumor promoting metabolic growth factors and cytokines, recapitulating changes that creates a tumor antagonizing environment. Immune profiling revealed that IF profoundly reshapes anti-cancer immunity by inducing increase in CD4+ and CD8+ cells, paralleled by enhanced antitumor Th1 and cytotoxic responses, by enhancing their metabolic fitness. Metabolic studies revealed that IF generated bioactive metabolite BHB which can be a potential substitute for simulating the antitumor benefits of IF. However, in a direct comparison, IF surpassed exogenous BHB therapy in improving survival and activating anti-tumor immune response. Thus, our data provides strong evidence for IF and its metabolic mediator BHB for ameliorating EOC progression and as a viable approach in maintaining and sustaining an effective anti-tumor T cell response.

Does Prophylactic Paraortic Lymph Node Irradiation Improve Outcomes in Women With Stage IIIC1 Endometrial Carcinoma?

PURPOSE: To evaluate the impact of prophylactic paraortic lymph node (PALN) radiation therapy (RT) on clinical outcomes in patients with International Federation of Obstetrics and Gynecology 2018 stage IIIC1 endometrial cancer (EC). METHODS AND MATERIALS: A multi-institutional retrospective study included patients with International Federation of Obstetrics and Gynecology 2018 stage IIIC1 EC lymph node assessment, status postsurgical staging, followed by adjuvant chemotherapy and RT using various sequencing regimens. Overall survival (OS) and recurrence-free survival (RFS) rates were estimated by the Kaplan-Meier method. Univariable and multivariable analysis were performed by Cox proportional hazard models for RFS/OS. In addition, propensity score matching was used to estimate the effect of the radiation field extent on survival outcomes. RESULTS: A total of 378 patients were included, with a median follow-up of 45.8 months. Pelvic RT was delivered to 286 patients, and 92 patients received pelvic and PALN RT. The estimated OS and RFS rates at 5 years for the entire cohort were 80% and 69%, respectively. There was no difference in the 5-year OS (77% vs 87%, P = .47) and RFS rates (67% vs 70%, P = .78) between patients treated with pelvic RT and those treated with pelvic and prophylactic PALN RT, respectively. After propensity score matching, the estimated hazard ratios (HRs) of prophylactic PALN RT versus pelvic RT were 1.50 (95% confidence interval, 0.71-3.19; P = .28) for OS and 1.24 (95% confidence interval, 0.64-2.42; P = .51) for RFS, suggesting that prophylactic PALN RT does not improve survival outcomes. Distant recurrence was the most common site of first recurrence, and the extent of RT field was not associated with the site of first recurrence (P = .79). CONCLUSIONS: Prophylactic PALN RT was not significantly associated with improved survival outcomes in stage IIIC1 EC. Distant metastasis remains the most common site of failure despite routine use of systemic chemotherapy. New therapeutic approaches are necessary to optimize the outcomes for women with stage IIIC1 EC.

A Multi-Institutional Analysis of Adjuvant Chemotherapy and Radiation Sequence in Women With Stage IIIC Endometrial Cancer.

PURPOSE: Our purpose was to evaluate the effect of sequence and type of adjuvant therapy for patients with stage IIIC endometrial carcinoma (EC) on outcomes. METHODS AND MATERIALS: In a multi-institutional retrospective cohort study, patients with stage IIIC EC who had surgical staging and received both adjuvant chemotherapy and radiation therapy (RT) were included. Adjuvant treatment regimens were classified as adjuvant chemotherapy followed by sequential RT (upfront chemo), which was predominant sequence; RT with concurrent chemotherapy followed by chemotherapy (concurrent); systemic chemotherapy before and after RT (sandwich); adjuvant RT followed by chemotherapy (upfront RT); or chemotherapy concurrent with vaginal cuff brachytherapy alone (chemo-brachy). Overall survival (OS) and recurrence-free survival (RFS) rates were estimated by the Kaplan-Meier method. RESULTS: A total of 686 eligible patients were included with a median follow-up of 45.3 months. The estimated 5-year OS and RFS rates were 74% and 66%, respectively. The sequence and type of adjuvant therapy were not correlated with OS or RFS (adjusted P = .68 and .84, respectively). On multivariate analysis, black race, nonendometrioid histology, grade 3 tumor, stage IIIC2, and presence of adnexal and cervical involvement were associated with worse OS and RFS (all P < .05). Regardless of the sequence of treatment, the most common site of first recurrence was distant metastasis (20.1%). Vaginal only, pelvic only, and paraortic lymph node (PALN) recurrences occurred in 11 (1.6%),15 (2.2 %), and 43 (6.3 %) patients, respectively. Brachytherapy alone was associated with a higher rate of PALN recurrence (15%) compared with external beam radiation therapy (5%) P < .0001. CONCLUSIONS: The sequence and type of combined adjuvant therapy did not affect OS or RFS rates. Brachytherapy alone was associated with a higher rate of PALN recurrence, emphasizing the role of nodal radiation for stage IIIC EC. The vast proportion of recurrences were distant despite systemic chemotherapy, highlighting the need for novel regimens.

The Impact of Adjuvant Management Strategies on Outcomes in Women With Early Stage Uterine Serous Carcinoma.

Objective To determine the impact of different adjuvant strategies on outcomes in women with early-stage uterine serous carcinoma (USC). Methods Our retrospective database for women with endometrial carcinoma was queried for women with 2009 International Federation of Gynecology and Obstetrics (FIGO) stages I-II USC who underwent surgical staging between January 1991 and April 2019 followed by adjuvant management (observation, radiation therapy (RT), chemotherapy (CT), or combined modality treatment (CRT)). Chi-square tests were performed to compare differences in outcome by type of adjuvant management. Recurrence-free survival (RFS), disease-specific survival (DSS), and overall survival (OS) were assessed by Kaplan-Meier and log-rank tests. Univariate and multivariate analyses (MVA) were performed to identify statistically significant predictors of survival endpoints. Results We identified 171 women who met our inclusion criteria. The median follow-up time was 70.5 months. Seventy-five percent of the study cohort was FIGO stage IA, 13% were stage IB, and 12% were stage II. All women underwent pelvic lymph node dissection with a median number of dissected lymph nodes of 14. Omentectomy was performed in 64% of patients. Adjuvant RT was utilized in 56% of women (65 patients received vaginal brachytherapy alone, 10 patients received pelvic RT, and 21 patients received a combination of both). The most commonly used chemotherapy regimen was carboplatin and paclitaxel with a median number of cycles of six. A total of 44% of the cohort received CRT, 12% received RT alone, 19% received chemo alone, and 25% were observed. Five-year RFS was 73% for those who received CRT, 84% for those who received RT alone, 68% for those who received CT alone, and 55% for those who were observed (p=0.13). Five-year DSS was 81%, 94%, 71%, and 60%, respectively (p=0.02). Five-year OS was 76%, 70%, 60%, and 56%, respectively (p=0.11). On MVA of OS and DSS, a higher percentage of myometrial invasion, the presence of lower uterine segment involvement, positive peritoneal cytology, and receipt of chemotherapy alone/observation were independent predictors of worse outcomes. The sole independent predictor of worse RFS on MVA was the presence of positive peritoneal cytology. Conclusion In this cohort of women with early-stage USC who underwent surgical staging, adjuvant radiation treatment with or without chemotherapy was associated with improved survival endpoints and trended toward improved recurrence rates.

Increased risk of recurrence in early-stage endometrial carcinoma after delays in adjuvant radiation treatment.

OBJECTIVE: The benefits of adjuvant radiation treatment after hysterectomy have been confirmed in select patients with early-stage endometrial carcinoma. The goal of this study was to evaluate the prognostic impact of the time interval between hysterectomy and starting adjuvant radiation treatment in patients with early-stage endometrial carcinoma. METHODS: Our database was searched for women with early-stage endometrioid endometrial cancer who received adjuvant radiation therapy after hysterectomy. The patients were classified into two groups based on the time interval to adjuvant radiation therapy (≤8 weeks or >8 weeks) after hysterectomy. Recurrence-free survival, disease-specific survival, and overall survival were compared between the two groups. RESULTS: Four hundred and sixty patients were identified. Median follow-up was 70.5 months (range 1-360). One hundred and seventy-six patients (38%) were 2009 International Federation of Gynecology and Obstetrics stage IA, 207 (45%) stage IB, and 77 (17%) stage II. Three hundred and fifty-four women (77%) received adjuvant radiation therapy within 8 weeks after hysterectomy. There was no statistically significant difference between the two groups in baseline demographics, disease and treatment characteristics, except for the modality of adjuvant radiation therapy. Patients who received adjuvant radiation therapy within 8 weeks experienced significantly less disease recurrence (9% vs 18%; p=0.01) and particularly less isolated vaginal recurrence (0% vs 6%, p=0.04). Five-year recurrence-free survival was 89% versus 80% (p=0.04), 5-year disease-specific survival was 93% for both groups, and 5-year overall survival was 86% versus 85% for patients who received adjuvant radiation therapy ≤8 and >8 weeks, respectively (p=0.88). CONCLUSION: Our study suggests that delaying adjuvant radiation therapy beyond 8 weeks after hysterectomy is associated with significantly more cancer recurrences for women with early-stage endometrial carcinoma.

Evolving oxygenation management reasoning in COVID-19.

The initial phase of the SARS-CoV-2 pandemic in the United States saw rapidly-rising patient volumes along with shortages in personnel, equipment, and intensive care unit (ICU) beds across many New York City hospitals. As our hospital wards quickly filled with unstable, hypoxemic patients, our hospitalist group was forced to fundamentally rethink the way we triaged and managed cases of hypoxemic respiratory failure. Here, we describe the oxygenation protocol we developed and implemented in response to changing norms for acuity on inpatient wards. By reflecting on lessons learned, we re-evaluate the applicability of these oxygenation strategies in the evolving pandemic. We hope to impart to other providers the insights we gained with the challenges of management reasoning in COVID-19.

Identification of a novel diagnostic gene expression signature to discriminate uterine leiomyoma from leiomyosarcoma.

Leiomyosarcomas are rare, aggressive tumors, which exhibit a poor prognosis regardless of stage. Pre-operative diagnosis can be difficult as leiomyosarcoma can mimic features of the more common, benign uterine leiomyoma. The goal of this study was to identify specific molecular markers to discriminate between uterine leiomyosarcomas and leiomyomas to facilitate timely, accurate diagnosis and treatment. Gene expression profiles of three leiomyosarcomas, leiomyomas, and normal myometrial tissue samples were analyzed using the Affymetrix Human Gene 1.0 ST Array. GC-robust multiarray average calculation and ANOVA statistical testing were used to identify differentially expressed genes. Sixty genes, with functional roles in tumor progression or suppression, exhibited divergent expression profiles in leiomyosarcomas and leiomyomas, compared to normal myometrium. Differential RNA and protein levels of seven genes, with the most discriminatory expression patterns, were confirmed by RTPCR and immunohistochemistry in an additional 10 leiomyosarcoma and 20 leiomyoma independent samples. CHI3L1, MELK, PRC1, TOP2A, and TPX2 were overexpressed in leiomyosarcomas, while HPGD and TES were overexpressed in leiomyomas. Distinguishing leiomyosarcomas from leiomyomas represents a diagnostic challenge, particularly in the context of minimally invasive surgery. The unique gene expression signatures identified in this study may accurately differentiate between these tumor types at the earliest stage and provides potential prognostic factors and novel therapeutic targets for the treatment of leiomyosarcoma.

Work ability of aging teachers in Bulgaria.

OBJECTIVES: The work ability of aging teachers is of special interest because of high risk of stress. The aim of the study was to follow the work ability of aging teachers and compare it with that of aging non-teacher professionals. MATERIAL AND METHODS: The study included 424 teachers of age ≤ 44 years old (N = 140) and ≥ 45 years old (N = 284), with about 10% male teachers in both age groups, matched by sex and age with non-teacher professionals. Work ability was assessed by means of the Work Ability Index (WAI). Chi2 tests and regression analyses were used for studying WAI scales ratings, diagnosed by physician diseases and WAI ratings. RESULTS: Our data shows comparatively high work ability for both age groups of teachers but WAI of aging teachers was significantly lower in comparison to their younger colleagues as well as aging non-teacher professionals. About 80% of aging groups reported diseases diagnosed by physicians. Cardiovascular, musculoskeletal and respiratory diseases were the most frequently reported by aging teachers, while teachers ≤ 44 years old reported respiratory, cardiovascular, neurological and sensory diseases. With aging significantly higher rates of arterial hypertension, diabetes, injury to hearing and mental disorders were reported by teachers as compared to aging non-teacher professionals. The rates of reported repeated infections of respiratory tracts were high in both age groups of teachers, especially in the group of aging teachers. The estimated work ability impairment due to the disease showed the significant effect of aging for teachers as well as the significant difference when comparing aging teachers and non-teacher professionals. CONCLUSIONS: Our data shows high work ability for both age groups of teachers but significantly lower for aging teachers accompanied with higher rates of psychosomatic diseases, including hearing impairment and respiratory diseases. Preservation of teacher health could contribute to maintenance of their work ability and retention in the labor market. Int J Occup Med Environ Health 2018;31(5):593-602.

Dysphagia in the Elderly.

OPINION STATEMENT: Dysphagia is a common problem in the elderly population with an especially high prevalence in hospitalized and institutionalized patients. If inadequately addressed, dysphagia leads to significant morbidity and contributes to decreased quality of life. Dysphagia can be categorized as emanating from either an oropharyngeal or esophageal process. A disproportionate number of elderly patients suffer from oropharyngeal dysphagia with a multifactorial etiology. Historically, treatment options have been limited and included mostly supportive care with a focus on dietary modification, food avoidance, and swallow rehabilitation. Nascent technologies such as the functional luminal imaging probe (FLIP) and advances in esophageal manometry are improving our understanding of the pathophysiology of oropharyngeal dysphagia. Recent developments in the treatment of specific causes of oropharyngeal dysphagia, including endoscopic balloon dilations for upper esophageal sphincter (UES) dysfunction, show promise and are expected to enhance with further research. Esophageal dysphagia is also common in the elderly and more commonly due to an identifiable cause. The full breadth of treatment options is frequently unavailable to elderly patients due to comorbidities and overall functional status. However, the increasing availability of less invasive solutions to specific esophageal pathologies has augmented the number of treatment options available to this population, where an individualized approach to patient care is paramount. This review focuses on the evaluation and management of dysphagia in the elderly and delineates how standard and novel therapeutics are contributing to more nuanced and personalized management.

Asbestos exposure and mesothelioma incidence and mortality in Bulgaria.

Bulgaria totally banned the import, production and use of asbestos in 2005, but produced and used asbestos products during the last 3-4 decades of the 20th century. The aim of this study was to follow the incidence and mortality of mesothelioma in Bulgaria in relation to past occupational exposures. A literature search between 1960 and 2014 was conducted to obtain information on asbestos consumption, occupational exposure and asbestos-related diseases (ARDs). Data on registered mesotheliomas were provided by the National Cancer Register and data for recognized occupational ARDs were provided by the National Social Security Institute. An increase in the incidence of mesothelioma from 5 to 58 from 1993 to 2013, with 666 cases in the 21-year period, was registered. Incidence, mortality rates, deaths and male-to-female ratios and were lower in comparison to industrialized countries. The increase in mesothelioma incidence is considered as a consequence of more recent production and use of asbestos and asbestos products and the high occupational exposure between 1977 and 1989, while the lower rate of mesothelioma deaths and male-to-female ratio need to be investigated further.

20-HETE induces remodeling of renal resistance arteries independent of blood pressure elevation in hypertension.

20-Hydroxyeicosatetraenoic acid (20-HETE) is a cytochrome P-450 (Cyp)-derived arachidonic acid metabolite that has been shown to increase smooth muscle contractions and proliferation, stimulate endothelial dysfunction and activation, and promote hypertension. We examined if 20-HETE contributes to microvascular remodeling in hypertension. In Sprague-Dawley rats, administration of the 20-HETE biosynthesis inhibitor HET0016 or the 20-HETE antagonist N-20-hydroxyeicosa-6(Z),15(Z)-dienoic acid (20-HEDE) prevented 5α-dihydrotestosterone (DHT)-induced increases in blood pressure as well as abrogated DHT-induced increases in the media-to-lumen ratio (M/L), media thickness, and collagen IV deposition in renal interlobar arteries. Reserpine prevented blood pressure elevation in DHT-treated rats but did not affect microvascular remodeling (M/L, media thickness, and collagen deposition); under these conditions, treatment with the 20-HETE antagonist attenuated microvascular remodeling, suggesting that 20-HETE contributes to DHT-induced vascular remodeling independent of blood pressure elevation. In Cyp4a14(-/-) mice, which display androgen-driven and 20-HETE-dependent hypertension, treatment with the 20-HETE antagonist abolished remodeling of renal resistance arteries measured as media thickness (24 ± 1 vs. 15 ± 1 µm) and M/L (0.29 ± 0.03 vs. 0.17 ± 0.01). Moreover, in Cyp4a12 transgenic mice in which the expression of Cyp4a12-20-HETE synthase is driven by a tetracycline-sensitive promoter, treatment with doxycycline resulted in blood pressure elevation (140 ± 4 vs. 92 ± 5 mmHg) and a significant increase in remodeling of renal resistance arteries (media thickness: 23 ± 1 vs. 16 ± 1 µm; M/L: 0.39 ± 0.04 vs. 0.23 ± 0.02); these increases were abrogated by cotreatment with 20-HEDE. This study demonstrated that 20-HETE is a key regulator of microvascular remodeling in hypertension; its effect is independent of blood pressure elevation and androgen levels.

Restoration of miR-200c to ovarian cancer reduces tumor burden and increases sensitivity to paclitaxel.

A therapeutic intervention that could decrease tumor burden and increase sensitivity to chemotherapy would have a significant impact on the high morbidity rate associated with ovarian cancer. miRNAs have emerged as potential therapeutic candidates due to their ability to downregulate multiple targets involved in tumor progression and chemoresistance. miRNA-200c (miR-200c) is downregulated in ovarian cancer cell lines and stage III ovarian tumors, and low miR-200c correlates with poor prognosis. miR-200c increases sensitivity to taxanes in vitro by targeting class III ß-tubulin gene (TUBB3), a tubulin known to mediate chemoresistance. Indeed, we find that patients with tumors having low TUBB3 had significantly prolonged survival (average survival 52.73 ± 4.08 months) as compared with those having high TUBB3 (average survival 42.56 ± 3.19 months). miR-200c also targets TrkB, a mediator of resistance to anoikis. We show that restoration of miR-200c to ovarian cancer cells results in increased anoikis sensitivity and reduced adherence to biologic substrates in vitro. Because both chemo- and anoikis-resistance are critical steps in the progression of ovarian cancer, we sought to determine how restoration of miR-200c affects tumor burden and chemosensitivity in an in vivo preclinical model of ovarian cancer. Restoration of miR-200c in an intraperitoneal xenograft model of human ovarian cancer results in decreased tumor formation and tumor burden. Furthermore, even in established tumors, restoration of miR-200c, alone or in combination with paclitaxel, results in significantly decreased tumor burden. Our study suggests that restoration of miR-200c immediately before cytotoxic chemotherapy may allow for a better response or lower effective dose.

Characterization of the uterine leiomyoma microRNAome by deep sequencing.

MicroRNAs (miRNAs) are a class of small non-coding RNAs, which are negative regulators of gene expression. Many genes in human uterine leiomyoma (ULM) are aberrantly expressed and in some cases this can be due to dysregulation of miRNAs. Here we present the first study to determine genome-wide miRNA expression patterns in uterine leiomyoma and myometrium using Solexa high-throughput sequencing. We found more than 50 miRNAs, which were differentially expressed, and furthermore we extend the list of putative new miRNA genes. The top five significantly de-regulated miRNAs in ULMs that we found in our libraries were miR-363, miR-490, miR-137, miR-217 and miR-4792. We also observed "isomiRs" with higher copy number than referenced mature miRNA specific for the leiomyoma libraries, which have a potential role in tumorigenesis. The microRNA transcriptomes obtained in this study deliver insights and further expand our understanding the role of small RNAs in uterine leiomyoma development.

Gene expression profiling of multiple leiomyomata uteri and matched normal tissue from a single patient.

OBJECTIVE: To identify differentially expressed genes between fibroid and adjacent normal myometrium in an identical hormonal and genetic background. DESIGN: Array analysis of three leiomyomata and matched adjacent normal myometrium in a single patient. SETTING: University of Colorado Hospital. PATIENT(S): A single female undergoing medically indicated hysterectomy for symptomatic fibroids. INTERVENTIONS(S): mRNA isolation and microarray analysis, reverse-transcriptase polymerase chain reaction, Western blotting, and immunohistochemistry. MAIN OUTCOME MEASURE(S): Changes in mRNA and protein levels in leiomyomata and matched normal myometrium. RESULT(S): Expression of 197 genes was increased and 619 decreased significantly by at least twofold, in leiomyomata relative to normal myometrium. Expression profiles between tumors were similar and normal myometrial samples showed minimal variation. Changes in, and variation of, expression of selected genes were confirmed in additional normal and leiomyoma samples from multiple patients. CONCLUSION(S): Analysis of multiple tumors from a single patient confirmed changes in expression of genes described in previous, apparently disparate, studies, and identified novel targets. Gene expression profiles in leiomyomata are consistent with increased activation of mitogenic pathways and inhibition of apoptosis. Down-regulation of genes implicated in invasion and metastasis, of cancers, was observed in fibroids. This expression pattern may underlie the benign nature of uterine leiomyomata and may aid in the differential diagnosis of leiomyosarcoma.

Analysis of protein kinase C delta (PKC delta) expression in endometrial tumors.

Endometrial cancer is the most common gynecologic malignancy in the United States. However, its underlying molecular mechanisms are poorly understood; and few prognostic indicators have been identified. The protein kinase C (PKC) family has been shown to regulate pathways critical to malignant transformation; and in endometrial tumors, changes in PKC expression and activity have been linked to a more aggressive phenotype and poor prognosis. We have recently shown that PKC delta is a critical regulator of apoptosis and cell survival in endometrial cancer cells; however, PKC delta levels in endometrial tumors had not been determined. We used immunohistochemistry to examine PKC delta protein levels in normal endometrium and endometrioid carcinomas of increasing grade. Normal endometrium exhibited abundant nuclear and cytoplasmic staining of PKC delta confined to glandular epithelium. In endometrial tumors, decreased PKC delta expression, both in intensity and fraction of epithelial cells stained, was observed with increasing tumor grade, with PKC delta being preferentially lost from the nucleus. Consistent with these observations, endometrial cancer cell lines derived from poorly differentiated tumors exhibited reduced PKC delta levels relative to well-differentiated lines. Treatment of endometrial cancer cells with etoposide resulted in a translocation of PKC delta from cytoplasm to nucleus concomitant with induction of apoptosis. Decreased PKC delta expression, particularly in the nucleus, may compromise the ability of cells to undergo apoptosis, perhaps conferring resistance to chemotherapy. Our results indicate that loss of PKC delta is an indicator of endometrial malignancy and increasing grade of cancer. Thus, PKC delta may function as a tumor suppressor in endometrial cancer.

Expression of Bax in yeast affects not only the mitochondria but also vacuolar integrity and intracellular protein traffic.

Bax-induced lethality in yeast is accompanied by morphological changes in mitochondria, giving rise to a reduced number of swollen tubules. Although these changes are completely abolished upon coexpression of the Bax inhibitor, Bcl-2, coexpression of Bax with Bax inhibiting-glutathione S-transferase (BI-GST) leads to aggregation, but not fusion of the mitochondria. In addition, Bax affects the integrity of yeast vacuoles, resulting in the disintegration and eventual loss of the organelles, and the disruption of intracellular protein traffic. While Bcl-2 coexpression only partially corrects this phenotype, coexpression of BI-GST fully restores the organelles, indicating a different mode of protection exerted by Bcl-2 and BI-GST.