ERBB2 (HER2) amplifications and co-occurring KRAS alterations in the circulating cell-free DNA of pancreatic ductal adenocarcinoma patients and response to HER2 inhibition.

Purpose: Despite accumulating data regarding the genomic landscape of pancreatic ductal adenocarcinoma (PDAC), olaparib is the only biomarker-driven FDA-approved targeted therapy with a PDAC-specific approval. Treating ERBB2(HER2)-amplified PDAC with anti-HER2 therapy has been reported with mixed results. Most pancreatic adenocarcinomas have KRAS alterations, which have been shown to be a marker of resistance to HER2-targeted therapies in other malignancies, though the impact of these alterations in pancreatic cancer is unknown. We describe two cases of ERBB2-amplified pancreatic cancer patients treated with anti-HER2 therapy and provide data on the frequency of ERBB2 amplifications and KRAS alterations identified by clinical circulating cell-free DNA testing. Methods: De-identified molecular test results for all patients with pancreatic cancer who received clinical cell-free circulating DNA analysis (Guardant360) between 06/2014 and 01/2018 were analyzed. Cell-free circulating DNA analysis included next-generation sequencing of up to 73 genes, including select small insertion/deletions, copy number amplifications, and fusions. Results: Of 1,791 patients with pancreatic adenocarcinoma, 36 (2.0%) had an ERBB2 amplification, 26 (72.2%) of whom had a KRAS alteration. Treatment data were available for seven patients. Two were treated with anti-HER2 therapy after their cell-free circulating DNA result, with both benefiting from therapy, including one with a durable response to trastuzumab and no KRAS alteration detected until progression. Conclusion: Our case series illustrates that certain patients with ERBB2-amplified pancreatic adenocarcinoma may respond to anti-HER2 therapy and gain several months of prolonged survival. Our data suggests KRAS mutations as a possible mechanism of primary and acquired resistance to anti-HER2 therapy in pancreatic cancer. Additional studies are needed to clarify the role of KRAS in resistance to anti-HER2 therapy.

Case Report: Long-term complete response to PSMA-targeted radioligand therapy and abiraterone in a metastatic prostate cancer patient.

Despite decades of research and clinical trials, metastatic castration-resistant prostate cancer (mCRPC) remains incurable and typically fatal. Current treatments may provide modest increases in progression-free survival but can come with significant adverse effects and are disaggregated from the diagnostic imaging needed to fully assess the spread of metastatic disease. A theranostic approach, using radiolabeled ligands that target the cell surface protein PSMA, simplifies the visualization and disease treatment process by enabling both to use similar agents. Here, we describe an exemplary case wherein a gentleman in his 70s with mCRPC on diagnosis was treated with 177Lu-PSMA-617 and abiraterone, and remains disease-free to date, over five years later.

Case report: ex vivo tumor organoid drug testing identifies therapeutic options for stage IV ovarian carcinoma.

Patients presenting with stage 4 ovarian carcinoma, including low-grade serous disease, have a poor prognosis. Although platinum-based therapies can offer some response, these therapies are associated with many side effects, and treatment resistance often develops. Toxic side effects along with disease progression render patients unable to receive additional lines of treatment and limit their options to hospice or palliative care. In this case report, we describe a patient with an unusual case of metastatic low-grade serous ovarian cancer with some features of high-grade disease who had received four previous lines of treatment and was suffering from atelectasis, pulmonary embolism, and hydronephrosis. A CLIA-certified drug sensitivity assay of an organoid culture derived from the patient's tumor (PARIS® test) identified several therapeutic options, including the combination of fulvestrant with everolimus. On this treatment regimen, the patient experienced 7 months of stable disease and survived nearly 11 months before succumbing to her disease. This case emphasizes the clinical utility of ex vivo drug testing as a new functional precision medicine approach to identify, in real-time, personalized treatment options for patients, especially those who are not benefiting from standard of care treatments.

Genomic Profiling Reveals Medullary Thyroid Cancer Misdiagnosed as Lung Cancer.

Mutations or other alterations in the RET gene have been implicated in a variety of malignancies - most commonly thyroid, but also chronic myelomonocytic leukemia, acute myeloid leukemia, and lung, breast, pancreatic, and colon cancers. Here we present a case of a gentlemen initially diagnosed with and treated for non-small cell lung adenocarcinoma. Genomic profiling of his tumor specimen revealed a RET point mutation with a known association with medullary thyroid cancer (MTC). Further pathological and molecular diagnostic evaluation confirmed a diagnosis of MTC, leading to a change in treatment from standard chemotherapy for non-small cell lung cancer to targeted therapy against RET and potential implications regarding inherited cancer risk for his offspring. The patient experienced a clinical response to treatment and several months of improved quality of life. This case illustrates the capacity of genomic profiling to uncover molecular drivers of disease and help ensure proper diagnosis and management of cancer.

Dissection of the dislocation pathway for type I membrane proteins with a new small molecule inhibitor, eeyarestatin.

The mammalian endoplasmic reticulum (ER)-to-cytosol degradation pathway for disposal of misfolded proteins is an attractive target for therapeutic intervention in diseases that are characterized by impaired protein degradation. The ability to do so is hampered by the small number of specific inhibitors available and by our limited understanding of the individual steps involved in this pathway. Cells that express a class I major histocompatibility complex (MHC) heavy chain-enhanced green fluorescent protein (EGFP) fusion protein and the human cytomegalovirus protein US11, which catalyzes dislocation of the class I MHC EGFP reporter, show only little fluorescence. Treatment with proteasome inhibitors increases their fluorescence by stabilizing EGFP-tagged MHC class I molecules. We used this change in signal intensity as a readout to screen a chemical library of 16,320 compounds and identified two structurally related compounds (eeyarestatin I and II) that interfered with the degradation of both EGFP-heavy chain and its endogenous unmodified class I MHC heavy chain counterpart. Eeyarestatin I also inhibited degradation of a second misfolded type I membrane protein, T-cell receptor alpha. Both compounds stabilize these dislocation substrates in the ER membrane, without preventing proteasomal turnover of cytosolic substrates. The new inhibitors must therefore interfere with a step that precedes proteasomal degradation. The use of eeyarestatin I thus allows the definition of a new intermediate in dislocation.

Examination of Duct Physiology in the Human Mammary Gland.

BACKGROUND: The human breast comprise several ductal systems, or lobes, which contain a small amount of fluid containing cells, hormones, proteins and metabolites. The complex physiology of these ducts is likely a contributing factor to the development of breast cancer, especially given that the vast majority of breast cancers begin in a single lobular unit. METHODS: We examined the levels of total protein, progesterone, estradiol, estrone sulfate, dehydroepiandrosterone sulfate, and macrophages in ductal fluid samples obtained from 3 ducts each in 78 women, sampled twice over a 6 month period. Samples were processed for both cytological and molecular analysis. Intraclass correlation coefficients and mixed models were utilized to identify significant data. RESULTS: We found that the levels of these ductal fluid components were generally uncorrelated among ducts within a single breast and over time, suggesting that each lobe within the breast has a distinct physiology. However, we also found that estradiol was more correlated in women who were nulliparous or produced nipple aspirate fluid. CONCLUSIONS: Our results provide evidence that the microenvironment of any given lobular unit is unique to that individual unit, findings that may provide clues about the initiation and development of ductal carcinomas.

Synthetic glycoprotein mimics inhibit L-selectin-mediated rolling and promote L-selectin shedding.

L-selectin is a leukocyte cell-surface protein that facilitates the rolling of leukocytes along the endothelium, a process that leads to leukocyte migration to a site of infection. Preventing L-selectin-mediated rolling minimizes leukocyte adhesion and extravasation; therefore, compounds that inhibit rolling may act as anti-inflammatory agents. To investigate the potential role of multivalent ligands as rolling inhibitors, compounds termed neoglycopolymers were synthesized that possess key structural features of physiological L-selectin ligands. Sulfated neoglycopolymers substituted with sialyl Lewis x derivatives (3',6-disulfo Lewis x or 6-sulfo sialyl Lewis x) or a sulfatide analog (3,6-disulfo galactose) inhibited L-selectin-mediated rolling of lymphoid cells. Functional analysis of the inhibitory ligands indicates that they also induce proteolytic release of L-selectin. Thus, their inhibitory potency may arise from their ability to induce shedding. Our data indicate that screening for compounds that promote L-selectin release can identify ligands that inhibit rolling.

A feasibility study of the intraductal administration of chemotherapy.

Preclinical data have shown the potential of the intraductal administration of chemotherapy for breast cancer prevention. Direct translation of this work has been stymied by the anatomical differences between rodents (one duct per teat) and women (5-9 ductal systems per breast). The objective of this phase I study was to show the safety and feasibility of intraductal administration of chemotherapy drugs into multiple ducts within one breast in women awaiting mastectomy for treatment of invasive cancer. Thirty subjects were enrolled in this dose escalation study conducted at a single center in Beijing, China. Under local anesthetic, one of two chemotherapy drugs, carboplatin or pegylated liposomal doxorubicin (PLD), was administered into five to eight ducts at three dose levels. Pharmacokinetic analysis has shown that carboplatin was rapidly absorbed into the bloodstream, whereas PLD, though more erratic, was absorbed after a delay. Pathologic analysis showed marked effects on breast duct epithelium in ducts treated with either drug compared with untreated ducts. The study investigators had no difficulty in identifying or cannulating ducts except in one case with a central cancer with subareolar involvement. This study shows the safety and feasibility of intraductal administration of chemotherapy into multiple ducts for the purpose of breast cancer prevention. This is an important step toward implementation of this strategy as a "chemical mastectomy", where the potential for carcinogenesis in the ductal epithelium is eliminated pharmacologically, locally, and without the need for surgery.

Intraductal therapy of ductal carcinoma in situ: a presurgery study.

INTRODUCTION: Ductal carcinoma in situ (DCIS) is a noninvasive breast cancer wherein malignant cells are confined within a ductal lobular unit. Although less than half the cases of DCIS will progress to invasive disease, most women are treated aggressively with surgery, radiation, and/or hormone therapy due to the inability to clinically evaluate the extent and location of the disease. Intraductal therapy, in which a drug is administered directly into the mammary duct through the nipple, is a promising approach for treating DCIS, but the feasibility of instilling drug into a diseased duct has not been established. PATIENTS AND METHODS: Four to 6 weeks before their scheduled surgery, 13 women diagnosed with DCIS were subjected to cannulation of the affected duct. After both the absence of perforation and presence of dye in the duct were confirmed by ductogram, pegylated liposomal doxorubicin was instilled. Histopathologic assessment was performed after surgery to assess the treatment effects. RESULTS: Of the 13 women enrolled in the study, 6 had their DCIS duct successfully cannulated without perforation and instilled with the drug. The treatment was well tolerated, and no serious adverse events have been reported. Biomarker studies indicated a general decrease in Ki-67 levels but an increase in annexin-1 and 8-hydroxydeoxyguanosine in the lumen of DCIS-containing ducts, which suggests a local response to pegylated liposomal doxorubicin treatment. CONCLUSIONS: Intraductal therapy offers a nonsurgical strategy to treat DCIS at the site of disease, potentially minimizing the adverse effects of systemic treatment while preventing development of invasive cancer.

Transdermal buprenorphine controls central neuropathic pain.

A 53-year-old male with peripheral sensorimotor neuropathy suffered an intracerebral hemorrhage resulting in right hemiparesis and hemisensory loss. Three months later, he developed constant and burning pain within the entire right side of his body. He was diagnosed with central pain syndrome and treated with antiepileptics and tricyclic antidepressants. Minimal analgesia was achieved, which was limited by intractable sedation and drowsiness. Patient was then treated with oral opioids (morphine and hydrocodone with acetaminophen) in escalating doses that produced cognitive impairment. After an opioid rotation was attempted, by switching morphine to transdermal fentanyl, there was no pain reduction or improved quality of life. A trial of buprenorphine was initiated, by administering transdermal patches in escalating doses in weekly intervals. Patient's pain was eventually successfully controlled with buprenorphine patch 60 µg/h every 7 days. His self-reported Visual Analogue Scale pain scores decreased from an average of 8/10 to 2/10 or less. Patient's overall function and participation in home activities increased. Buprenorphine is a partial µ-receptor and a κ-δ receptor antagonist known to block NMDA receptors and reduce hyperalgesia secondary to central sensitization.(1) Buprenorphine is also a partial agonist at the opioid receptor-like (ORL-1) receptor, which is found to be analgesic and antinociceptive at the level of the spinal cord.(1,2) The difference in analgesic responses between buprenorphine and other opioids may be due to different receptor G protein interactions and/or selective activation of neuronal K(ATP) channels by buprenorphine.(3) Deficient opening of K(ATP) channels has been shown to mediate neuropathic pain(4); therefore, activation of these channels by buprenorphine may contribute to its analgesic effect in neuropathic pain states wherein other opioids fail. More recently, there have been two case reports in which patients with neuropathic pain of different central etiology were successfully treated with buprenorphine.(5) Despite advances in understanding the pathology related to central pain, effective treatment options are limited. Buprenorphine may be an analgesic option for central pain management when opioids fail to reduce hypersensitivity or when patients exhibit intolerable side effects to other medications.

The physiology of the normal human breast: an exploratory study.

The physiology of the nonlactating human breast likely plays a key role in factors that contribute to the etiology of breast cancer and other breast conditions. Although there has been extensive research into the physiology of lactation, few reports explore the physiology of the resting mammary gland, including mechanisms by which compounds such as hormones, drugs, and potential carcinogens enter the breast ducts. The purpose of this study was to explore transport of exogenous drugs into ductal fluid in nonlactating women and determine if their concentrations in the fluid are similar to those observed in the breast milk of lactating women. We selected two compounds that have been well characterized during lactation, caffeine and cimetidine. Caffeine passively diffuses into breast milk, but cimetidine is actively transported and concentrated in breast milk. After ingestion of caffeine and cimetidine, 14 nonlactating subjects had blood drawn and underwent ductal lavage at five time points over 12 h to measure drug levels in the fluid and blood. The concentrations of both caffeine and cimetidine in lavage fluid were substantially less than those observed in breast milk. Our results support recent evidence that the cimetidine transporter is not expressed in the nonlactating mammary gland, and highlight intriguing differences in the physiology and molecular transport of the lactating and nonlactating breast. The findings of this exploratory study warrant further exploration into the physiology of the nonlactating mammary gland to elucidate factors involved in disease initiation and progression.

The physiology of the normal human breast: an exploratory study

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The physiology of the nonlactating human breast likely plays a key role in factors that contribute to the etiology of breast cancer and other breast conditions. Although there has been extensive research into the physiology of lactation, few reports explore the physiology of the resting mammary gland, including mechanisms by which compounds such as hormones, drugs, and potential carcinogens enter the breast ducts. The purpose of this study was to explore transport of exogenous drugs into ductal fluid in nonlactating women and determine if their concentrations in the fluid are similar to those observed in the breast milk of lactating women. We selected two compounds that have been well characterized during lactation, caffeine and cimetidine. Caffeine passively diffuses into breast milk, but cimetidine is actively transported and concentrated in breast milk. After ingestion of caffeine and cimetidine, 14 nonlactating subjects had blood drawn and underwent ductal lavage at five time points over 12 h to measure drug levels in the fluid and blood. The concentrations of both caffeine and cimetidine in lavage fluid were substantially less than those observed in breast milk. Our results support recent evidence that the cimetidine transporter is not expressed in the nonlactating mammary gland, and highlight intriguing differences in the physiology and molecular transport of the lactating and nonlactating breast. The findings of this exploratory study warrant further exploration into the physiology of the nonlactating mammary gland to elucidate factors involved in disease initiation and progression (AU)