Current and emerging therapeutic options in adrenocortical cancer treatment

The Role of Fascin-1 in Human Urologic Cancers: A Promising Biomarker or Therapeutic Target?

Human cancer statistics show that an increased incidence of urologic cancers such as bladder cancer, prostate cancer, and renal cell carcinoma. Due to the lack of early markers and effective therapeutic targets, their prognosis is poor. Fascin-1 is an actin-binding protein, which functions in the formation of cell protrusions by cross-linking with actin filaments. Studies have found that fascin-1 expression is elevated in most human cancers and is related to outcomes such as neoplasm metastasis, reduced survival, and increased aggressiveness. Fascin-1 has been considered as a potential therapeutic target for urologic cancers, but there is no comprehensive review to evaluate these studies. This review aimed to provide an enhanced literature review, outline, and summarize the mechanism of fascin-1 in urologic cancers and discuss the therapeutic potential of fascin-1 and the possibility of its use as a potential marker. We also focused on the correlation between the overexpression of fascin-1 and clinicopathological parameters. Mechanistically, fascin-1 is regulated by several regulators and signaling pathways (such as long noncoding RNA, microRNA, c-Jun N-terminal kinase, and extracellular regulated protein kinases). The overexpression of fascin-1 is related to clinicopathologic parameters such as pathological stage, bone or lymph node metastasis, and reduced disease-free survival. Several fascin-1 inhibitors (G2, NP-G2-044) have been evaluated in vitro and in preclinical models. The study proved the promising potential of fascin-1 as a newly developing biomarker and a potential therapeutic target that needs further investigation. The data also highlight the inadequacy of fascin-1 to serve as a novel biomarker for prostate cancer.

Adrenal Tumors in Young Adults: Case Reports and Literature Review

The current high detection rate of adrenal tumors (4–10% of general population) is attributable to a widespread use of variety of imaging studies, especially a computed tomography. Most of them represent clinically silent and biologically indolent incidentalomas, but some adrenal tumors may pose a significant clinical challenge. Thus, in every patient with an adrenal tumor, a decision on further management is made after careful hormonal and radiological evaluation. All hormonally active tumors and those with radiological features suggesting malignancy are qualified for surgery. Approximately 80% of adrenal tumors are adrenocortical adenomas, hypertrophy, or nodular adrenocortical hyperplasia. Other histopathological diagnoses include pheochromocytoma, adrenocortical carcinoma, metastases, mesenchymal tumors, lymphomas, cysts, and ganglioneuromas. Adrenal tumors are more commonly diagnosed and better studied in elderly patients. In younger patients, under 40 years old, focal adrenal lesions are relatively rare, and histological distribution of diagnoses differs from that in elderly individuals. Younger patients are more likely to display endocrine symptoms, which raise the suspicion of an adrenal mass. In the current study, we present a case series of seven adrenal tumors occurring in young patients. The cases presented below, along with the literature review, demonstrate that the diagnosis and treatment of adrenal tumors are crucial due to endocrinopathy-derived complications and a potential risk of malignancy.

2D-DIGE proteomic analysis identifies new potential therapeutic targets for adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is a rare aggressive tumor with poor prognosis when metastatic at diagnosis. The tumor biology is still mostly unclear, justifying the limited specificity and efficacy of the anti-cancer drugs currently available. This study reports the first proteomic analysis of ACC by using two-dimensional-differential-in-gel-electrophoresis (2D-DIGE) to evaluate a differential protein expression profile between adrenocortical carcinoma and normal adrenal. Mass spectrometry, associated with 2D-DIGE analysis of carcinomas and normal adrenals, identified 22 proteins in 27 differentially expressed 2D spots, mostly overexpressed in ACC. Gene ontology analysis revealed that most of the proteins concurs towards a metabolic shift, called the Warburg effect, in adrenocortical cancer. The differential expression was validated by Western blot for Aldehyde-dehydrogenase-6-A1,Transferrin, Fascin-1,Lamin A/C,Adenylate-cyclase-associated-protein-1 and Ferredoxin-reductase. Moreover, immunohistochemistry performed on paraffin-embedded ACC and normal adrenal specimens confirmed marked positive staining for all 6 proteins diffusely expressed by neoplastic cells, compared with normal adrenal cortex.

In conclusion, our preliminary findings reveal a different proteomic profile in adrenocortical carcinoma compared with normal adrenal cortex characterized by overexpression of mainly metabolic enzymes, thus suggesting the Warburg effect also occurs in ACC. These proteins may represent promising novel ACC biomarkers and potential therapeutic targets if validated in larger cohorts of patients.

Synthetic high-density lipoprotein nanoparticles: A novel therapeutic strategy for adrenocortical carcinomas

BACKGROUND

Chemotherapeutic strategies for adrenocortical carcinoma (ACC) carry substantial toxicities. Cholesterol is critical for ACC cell growth and steroidogenesis, and ACC cells overexpress scavenger receptor BI, which uptakes cholesterol from circulating high-density lipoprotein (HDL) cholesterol. We hypothesize that cholesterol-free synthetic-HDL nanoparticles (sHDL) will deplete cholesterol and synergize with chemotherapeutics to achieve enhanced anticancer effects at lesser (less toxic) drug levels.

METHODS

The antiproliferative efficacy of ACC cells for the combinations of sHDL with chemotherapeutics was tested by Cell-Titer Glo. Cortisol levels were measured from the culture media. Effects on steroidogenesis was measured by real-time polymerase chain reaction (RT-PCR). Induction of apoptosis was evaluated by flow cytometry.

RESULTS

Combination Index (CI) for sHDL and either etoposide (E), cisplatin (P), or mitotane (M) demonstrated synergy (CI < 1) for antiproliferation. Alone or in combination with the chemotherapy drugs, sHDL was able to decrease cortisol production by 70-90% compared with P alone or controls (P < .01). RT-PCR indicated inhibition of steroidogenic enzymes for sHDL (P < .01 vs no sHDL). Combination therapy with sHDL increased apoptosis by 30-50% compared with drug or sHDL alone (P < .03), confirmed by a decrease in the mitochondrial potential.

CONCLUSION

sHDL can act synergistically and lessen the amount of M/E/P needed for anticancer efficacy in ACC in part owing to cholesterol starvation. This novel treatment strategy warrants further investigation translationally.

Pure aldosterone-secreting adrenocortical carcinoma in a patient with refractory primary hyperaldosteronism

We describe a young male patient with longstanding hypertension, who was diagnosed with primary hyperaldosteronism and treated by an attempted retroperitoneoscopic total unilateral adrenalectomy for a left-sided presumed aldosterone-secreting adenoma. Imaging had shown an unremarkable focal adrenal lesion with normal contralateral adrenal morphology, and histology of the resected specimen showed no adverse features. Post-operatively, his blood pressure and serum aldosterone levels fell to the normal range, but 9 months later, his hypertension recurred, primary aldosteronism was again confirmed and he was referred to our centre. Repeat imaging demonstrated an irregular left-sided adrenal lesion with normal contralateral gland appearances. Adrenal venous sampling was performed, which supported unilateral (left-sided) aldosterone hypersecretion. Redo surgery via a laparoscopically assisted transperitoneal approach was performed and multiple nodules were noted extending into the retroperitoneum. It was thought unlikely that complete resection had been achieved. His blood pressure returned to normal post-operatively, although hypokalaemia persisted. Histological examination, from this second operation, showed features of an adrenocortical carcinoma (ACC; including increased mitoses and invasion of fat) that was assessed as malignant using the scoring systems of Weiss and Aubert. Biochemical hyperaldosteronism persisted post-operatively, and detailed urine steroid profiling showed no evidence of adrenal steroid precursors or other mineralocorticoid production. He received flank radiotherapy to the left adrenal bed and continues to receive adjunctive mitotane therapy for a diagnosis of a pure aldosterone-secreting ACC.

Borderline resectable adrenal cortical carcinoma: a potential role for preoperative chemotherapy

BACKGROUND

Adrenal cortical carcinoma (ACC) may have tumor or patient characteristics at presentation that argue against immediate surgery because of an unacceptable risk of morbidity/mortality, incomplete resection, or recurrence. This clinical stage can be characterized as borderline resectable ACC (BRACC). At present, systemic therapies in ACC can reduce tumor burden in some patients, creating an opportunity in BRACC for a strategy of preoperative chemotherapy (ctx) followed by surgery.

MATERIALS AND METHODS

A single-institution retrospective review was conducted of all patients considered for surgery for primary ACC. Patients with BRACC treated with preoperative ctx were categorized as follows: group A, imaging suggesting a need for multiorgan/vascular resection; group B, imaging suggesting potentially resectable oligometastases; and group C, patients having marginal performance status/comorbidities precluding immediate surgery. Both the disease-free survival (DFS) and the overall survival (OS) were compared in BRACC patients treated with preoperative ctx+surgery and those who had upfront surgery.

RESULTS

Fifty-three patients with primary ACC were considered for surgery (median follow-up: 49.9 months). Thirty-eight patients (71.7 %) had initial surgery and 15 of them (28.3 %) were considered BRACC and received preoperative therapy. Of these 15 patients, 12 (80 %) received combination therapy with mitotane and etoposide/cisplatin-based ctx, 2 (13 %) received mitotane alone, and 1 (7 %) received ctx alone. Six patients were defined as group A, 5 as group B, and 4 as group C. Thirteen (87 %) BRACC patients underwent surgical resection. BRACC patients were younger but had more advanced disease than the patients having initial surgery (stage IV in 40 vs 2.6 % [p < 0.01]). By Response Evaluation Criteria In Solid Tumors criteria, 5 patients (38.5 %) had a partial response, 7 (53.8 %) had stable disease, and 1 (7.7 %) had disease that progressed. Postoperative mitotane use was similar between groups (p = .15). Median DFS for resected BRACC patients was 28.0 months [95 % confidence interval (CI), 2.9-not attained] vs 13 months (95 % CI, 5.8-46.9) (p = 0.40) for initial surgery patients. Five-year OS rates were also similar: 65 % for resected BRACC vs 50 % for initial surgery (p = 0.72).

CONCLUSIONS

The favorable outcome of patients with BRACC, despite more advanced stage of disease compared to those treated with surgery first, together with uncommon disease progression, suggests a benefit of neoadjuvant treatment sequencing in patients with BRACC.

Analysis of circulating microRNAs in adrenocortical tumors

Differential diagnosis of adrenocortical adenoma (ACA) and carcinoma is of pivotal clinical relevance, as the prognosis and clinical management of benign and malignant adrenocortical tumors (ACTs) is entirely different. Circulating microRNAs (miRNAs) are promising biomarker candidates of malignancy in several tumors; however, there are still numerous technical problems associated with their analysis. The objective of our study was to investigate circulating miRNAs in ACTs and to evaluate their potential applicability as biomarkers of malignancy. We have also addressed technical questions including the choice of profiling and reference gene used. A total of 25 preoperative plasma samples obtained from patients with ACAs and carcinomas were studied by microarray and quantitative real-time PCR. None of the three miRNAs (hsa-miR-192, hsa-mir-197 and hsa-miR-1281) found as differentially expressed in plasma samples in our microarray screening could be validated by quantitative real-time PCR. In contrast, of the selected eight miRNAs reported in the literature as differentially expressed in ACT tissues, five (hsa-miR-100, hsa-miR-181b, hsa-miR-184, hsa-miR-210 and hsa-miR-483-5p) showed a statistically significant overexpression in adrenocortical cancer vs adenoma when normalized on hsa-miR-16 as a reference gene. Receiver operator characteristic analysis of data revealed that the combination of dCThsa-miR-210 - dCThsa-miR-181b and dCThsa-miR-100/dCThsa-miR-181b showed the highest diagnostic accuracy (area under curve 0.87 and 0.85, respectively). In conclusion, we have found significant differences in expression of circulating miRNAs between ACAs and carcinomas, but their diagnostic accuracy is not yet high enough for clinical application. Further studies on larger cohorts of patients are needed to assess the diagnostic and prognostic potential application of circulating miRNA markers.