Radium-223 for mCRPC, a real-world experience study from 7 Galician medical centers

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Background: Radium-223 represents an option for symptomatic metastatic castration-resistant prostate cancer (mCRPC) after demonstrated an overall survival improvement in the ALSYMPCA trial. Radium-223 real-life experiences are scarce, particularly after the results of the ERA-223 trial. To describe Radium-223 outcomes in real life practice, and specifically those related with bone health, sequence of treatment, and prognostic factors. Methods: Multicenter retrospective study of a cohort of 143 patients with mCRPC treated with Radium-223 in either the second line or third line of therapy or beyond in the context of routine clinical practice between 11 March 2013 and 26 July 2022, in seven Galician hospitals. Survival estimates were calculated by the Kaplan-Meier method, and groups were compared with the log-rank test. The Cox proportional hazards regression model was used to evaluate factors independently associated with OS. Between March 11, 2013, and July 26, 2022, 143 patients were enrolled from 5 Galician hospitals. With a median follow-up of 9.68 months. All patients signed an informed consent form agreeing to participate in this observational study, that was approved by the Galician Ethics Committee, registration code 2018/282. Results: Baseline patient and disease characteristics are summarized. Median follow-up was 9.68 months. Median overall survival (OS) was 12 months (95% CI 9.7 – 16.0). Best OS outcomes were achieved in second and third line, 18 months (95% CI 12.0 – 26.0) and 9.4 months (95% CI 8.0 – 12.0) months, respectively. Among those baseline clinic-analytical factors analyzed, only alkaline phosphatase level >354 UI/L was correlated with a worse OS (HR 2.56 (95% CI 1.39 – 4.72; p=0.003) and the number of cycles of Radium-223 received (HR 0.63 (95% CI 0.54 – 0.73; p<0.001) were prognostic factors for Radium-223. Importantly, ninety-nine of patients (80%) were treated with bone-targeted therapy for bone metastases with no OS differences (p=0.66). Conclusions: In our study, Radium-223 efficacy was consistent with previously reported. Best efficacy was achieved in the second or third line of therapy, independently of docetaxel use. Patients with high baseline alkaline phosphatase had worse OS. Few patients presented skeletal-related events, which could be explained by an adequate use of bone-targeted therapy (zoledronic acid or denosumab). [Table: see text]

Real-world efficacy and safety of peptide receptor radionuclide therapy (PRRT) in gastroenteropancreatic neuroendocrine tumors (GEP-NETs)

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Background: PRRT with 177Lu-Dotatate (Lutathera) is a radiolabeled somatostatin analog indicated treatment of somatostatin receptor (STTR) positive GEP-NETs. The study aims to establish the efficacy and safety of PRRT in GEP-NETs in a real-world setting. Methods: We conducted an observational, retrospective, multicentric study of 40 patients with GEP-NET treated with PRRT belonging to GGNET (Galician Research Group on Neuroendocrine Tumors) network at Nuclear Medicine Department of Santiago de Compostela University Hospital (Spain). Patients characteristics, overall survival (OS), progression-free survival (PFS), overall response rate (ORR) and toxicity data were retrospectively collected and analyzed. Results: Data from 40 patients (pts) treated between 2016 and 2020 were recorded in this study. Median age was 63.5 years (range 41-85) and 55% were male. The baseline ECOG PS 0/1/2 was 15 (37.5%)/16 (40%)/9 (22.5%). Tumor location was intestinal 26 pts (65%), pancreas in 11 pts (27.5%) and unknown origin in 3 pts (7.5%). 25 pts (62.5%) were none functioning. Tumor grade G1/G2/G3 were 17 pts (42.5%)/ 20 pts (50%)/ 3 pts (7.5%), and Ki 67 < 2/3-20/ > 20%/unknown was 11 pts (27.5%)/ 21 pts (52.5%)/ 3 pts (7.5%)/ 5 pts (12.5%), respectively. The most frequent site of metastasis was liver in 32 pts (80%), lymph nodes in 19 pts (47.5%), peritoneum 11 pts (27.5%) and bone 10 pts (25%). Surgery: 22 pts (55%) primary tumor surgery and 8 pts (20%) metastasectomy. Previous systemic treatments included somatostatin analogs (SSA) in 40 pts (100%), everolimus in 26 pts (65%) and sunitnib in 11 pts (27.5%), others 7 pts (17.5%). 34 pts (85%) completed 4 cycles of treatment (6 pts (15%) non-complete due to premature death). 35 pts were evaluable for early response (after 2 cycles of treatment). Early ORR and DCR were 2.8% and 74.2%, respectively. 26 pts were evaluable after finishing treatment (6 pts premature death and 8 pending evaluation). ORR and DCR were 19.2% and 92.3%. With a median follow up of 21 months, 14 pts (35%) had died. Median OS was not reached (NR) and median PFS was 27.2 m (95% CI 16.0-38.4m). Tumor grade G1-2 (p < 0.001), Ki 67 <20% (p = 0.002), primary tumor surgery (p = 0.039) and metastasectomy (p = 0.030) were associated with prolonged PFS. Mild adverse events were most frequent after the 1º doses in 27.5% patients, and medium-term toxicity was present in 25.6%, mainly hematological, G1-G2 25.6%, and G3 5%. Conclusions: 177Lu-Dotatate is a safe and effective treatment for those patients diagnosed with metastatic GEP-NET and positive somatostatin receptors, with an excellent clinical and radiological response. Furthermore, we have identified some predictive factors to OS that should be taken into consideration.

The role of systemic inflammatory factors in gastroenteropancreatic neuroendocrine tumors (GEP-NETs) treated with peptide receptor radionuclide therapy (PRRT)

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Background: Inflammation plays a key role in the pathophysiology of many diseases, including cancer. Systemic inflammatory factors have been validated as indicators of ongoing systemic inflammation that could be predictive markers of poor prognosis for oncological outcomes. However, it is unknown the prognostic impact of systemic inflammation markers in patients with GEP-NETs treated with PRRT. Methods: We conducted an observational, retrospective, multicentric study of 40 patients with GEP-NET treated with PRRT belonging to GGNET (Galician Research Group on Neuroendocrine Tumors) network at Nuclear Medicine Department of Santiago de Compostela University Hospital (Spain). The systemic inflammatory markers were calculated as follows: NLR = neutrophil count/lymphocyte count, PLR = platelet count/lymphocyte count, MLR= monocyte count/lymphocyte count, ALB= albumin levels and dNLR = neutrophil count/ (leucocytes count – neutrophils count). For the calculation of the different ratios, baseline analysis and after the second dose were used. The cut-off values were determined as the median of each values, correlating them with progression-free survival (PFS). Results: Data from 40 patients (pts) treated between 2016 and 2020 were recorded. Median age was 63.5 years (range 41-85) and 55% were male. Baseline ECOG PS 0/1/2 was 15 (37.5%)/16 (40%)/9 (22.5%). Tumor location was intestinal 26 pts (65%), pancreas 11 pts (27.5%) and unknown origin 3 pts (7.5%). 15 pts (37.5%) were functioning. Tumor grade G1/G2/G3 were 17 pts (42.5%)/ 20 pts (50%)/ 3 pts (7.5%), and Ki 67 <2/3-20/>20%/unknown were 11 pts (27.5%)/ 21 pts (52.5%)/ 3 pts (7.5%)/ 5 pts (12.5%), respectively. The most frequent site of metastasis was liver 32 pts (80%), lymph nodes 19 pts (47.5%), peritoneum 11 pts (27.5%) and bone 10 pts (25%). Surgery: 22 pts (55%) primary tumor surgery and 8 pts (20%) metastasectomy. Previous systemic treatments included somatostatin analogs (SSA) 40 pts (100%), everolimus 26 pts (65%) and sunitnib 11 pts (27.5%), others 7 pts (17.5%). The baseline cutoff-values for NLR was 2.61, for PLR 110.14, for MLR 0.31, for ALB 4.2. and for dNLR 1.71. The cutoff-values after the 2nd dose for NLR was 2.3, for PLR 2.15, for MLR 0.3, for ALB 4.2 and for dNLR 1.48. With a median follow up of 21 months, 14 pts (35%) had died. Median PFS was 27.2 m (95% CI 16.0-38.4m) and OS was not reached (NR). Pts with baseline higher NLR (>2.61 vs. <2.61) had a significantly lower PFS: 15.8 m vs. NR (HR 0.181; 95% CI 0.051-0.638, p=0.03), which was also true for pts with elevated dNLR (>1.71 vs. <1.71): PFS 15.8 m vs. NR (HR 0.174; 0.049-0.614, p=0.03). Baseline PLR, ALB, MLR and NLR, PLR, ALB, dNLR and MLR values after the 2nd dose was not statistically significant for PFS. Conclusions: We have identified that baseline NLR and dNRL are significant predictive factors in patients with GEP-NETs treated with PRRT.

Molecular analysis of Arachis interspecific hybrids

Incorporation of genetic resistance against several biotic stresses that plague cultivated peanut, Arachis hypogaea (2n = 4x = 40), is an ideal option to develop disease resistant and ecologically safe peanut varieties. The primary gene pool of peanut contains many diploid wild species (2n = 2x = 20) of Arachis, which have high levels of disease and insect resistances. However, transfer of resistant genes from these species into A. hypogaea is difficult due to ploidy level differences and genomic incompatibilities. This study was conducted to monitor alien germplasm transmission, using Random Amplified Polymorphic DNA (RAPD) markers, from two diploid wild species, A. cardenasii and A. batizocoi, into A. hypogaea. Triploid interspecific hybrids were produced by crossing two A. hypogaea cultivars (NC 6 and Argentine) with the two species and by colchicine-treating vegetative meristems, fertility was restored at the hexaploid (C(o)) level in the four hybrids. Hexaploids were allowed to self-pollinate for four generations, each referred to as a cycle (C1, C2, C3, and C4). At each cycle, a backcross was made with the respective A. hypogaea cultivar as the maternal parent and only lineages tracing back to a single hexaploid hybrid were used for RAPD analysis. Analysis of mapped, species-specific RAPD markers in BC1F1 to BC1F3 hybrids indicated that alien germplasm retention decreased every generation of inbreeding, especially in Argentine and in A. batizocoi crosses. A similar trend was also observed for every cycle in BC1F2 and BC1F3 families, possibly, due to the loss of alien chromosomes following selfing of hexaploids. RAPD marker analysis of 40-chromosome interspecific hybrid derivatives from the four crosses supported previous reports that reciprocal recombination and/or translocations are the predominant mechanisms for exchange of chromosomal segments. No evidence was found for preferential transfer of alien chromosomal regions to specific linkage groups. The implications for developing disease resistant peanut breeding lines are discussed in light of these findings.

Identification of RAPD, SCAR, and RFLP markers tightly linked to nematode resistance genes introgressed from Arachis cardenasii into Arachis hypogaea

Two dominant genes conditioning resistance to the root-knot nematode Meloidogyne arenaria were identified in a segregating F2 population derived from the cross of 4x (Arachis hypogaea x Arachis cardenasii)-GA 6 and PI 261942. Mae is proposed as the designation for the dominant gene restricting egg number and Mag is proposed as the designation for the dominant gene restricting galling. The high levels of resistance in GA 6 were introgressed from A. cardenasii and, therefore, a search to identify A. cardenasii specific RAPD markers that are tightly linked to these resistance genes was conducted utilizing bulked segregant analysis. One RAPD marker (Z3/265) was linked at 10 +/- 2.5 (SE) and 14 +/- 2.9 cM from Mag and Mae, respectively. The marker was mapped to linkage group 1 at 5 cM from Xuga.cr239 in the backcross map in an area where introgression from A. cardenasii had previously been reported. This fragment was cloned and used to generate a pair of primers that specifically amplified this locus (sequence characterized amplified region, SCAR) and as a RFLP probe. Their close linkage with the resistance genes will be useful in marker-based selection while transferring nematode resistance from introgression lines into elite breeding lines and cultivars. The Z3/265 marker associated with the genes Mae or Mag was not found in other highly resistant Arachis species (Arachis batizocoi or Arachis stenosperma), in progenies of interspecific crosses with A. cardenasii that were moderately resistant, or in the resistant A. hypogaea lines PI 259634 and PI 259572. These represent the first molecular markers linked with a resistant gene in peanut and the first report of two physiological responses to nematode attack associated with two genetic factors.

[Food poisoning outbreak caused by Salmonella Enteritidis in the northwest of São Paulo State, Brazil]

A foodborne outbreak which affected 211 persons occurred, in a School, in 1993. The epidemiological data obtained by interviewing the affected and non affected persons sampled showed as predominant symptoms: diarrhoea, fever (77.7%), abdominal cramps (67.7%), vomiting (65.8%), hot-and-cold sensations (54.5%) and headache (44.5%). The median incubation period was of 17 hours, the limits being 3 and 29 hours. The disease period was of from 3 to 4 days. The food concerned was a kind of paté, a mayonnaise mixture prepared with fresh eggs with boiled potatoes that was consumed with bread. The biological material analysis-3 coprocultures, and leftovers of the food revealed the presence of one and the same organism: Salmonella Enteritidis. In the food, the numbers of this bacterium per gram were sufficient to account for the manifestation of the disease (10(4) and 10(5)g). The antibiogram of all th isolates showed the same sensibility pattern. The preparation related to this outbreak suggests the endogenous contamination of the eggs; the cross contamination-the outbreak affected three school periods, as the food was prepared separately for each school period; and the conditions under which the food was kept during the time from preparation to consumption. The observation of the 3 food handlers, by successive coprocultures, for one week, indicates that they were not asymptomatic carriers nor were they affected as a result of this outbreak by the causal bacteria.

Introgression analysis of an interspecific hybrid population in peanuts (Arachis hypogaea L.) using RFLP and RAPD markers

Forty-six introgression lines (F10C9) from a cross between Arachis hypogaea L. (2n = 4x = 40) and A. cardenasii Krapov. & W. C. Gregory (2n = 2x = 20) were analyzed for the introgression of A. cardenasii chromosome segments. Seventy-three RFLP probes and 70 RAPD primers, expressing from one to four A. cardenasii-specific bands, were used to evaluate the set of introgression lines. Thirty-four RFLP probes and 45 RAPD primers identified putative A. cardenasii introgressed chromosome segments in one or more lines. Introgressed segments were detected by RFLP analysis in 10 of the 11 linkage groups; the smallest introgressed fragments were detected by single RFLP markers and the largest were detected by three or four adjacent markers and represented introgressed segments of 30-40 cM. Similar results were obtained with RAPD markers, although markers detecting introgressed fragments could not be placed on the peanut linkage map. Introgression into both A. hypogaea genomes was detected and its implication in breeding for disease resistance is discussed.

Epithelioid sarcoma. Flow cytometric study of DNA content and regional DNA heterogeneity

The DNA content and regional DNA heterogeneity in correlation with clinicopathologic parameters and patient survival were investigated in epithelioid sarcoma. Such neoplasms preponderantly manifest diploid DNA content and a remarkably stable intratumoral and intertumoral DNA content. Small tumor size (less than 5.0 cm) and low S-phase fraction (less than 5%) were significant prognostic factors in this study. Ploidy status, mitotic rate, age, and postsurgical treatment were not significantly correlated with survival.

Sinonasal hemangiopericytomas. A clinicopathologic and DNA content study

The clinicopathologic and the flow cytometric DNA characteristics of 14 patients with sinonasal hemangiopericytomas are presented. Patient and tumor characteristics were similar to previously published series. Flow cytometric analysis revealed a diploid DNA pattern and low S-phase in 13 neoplasmas and an aneuploid DNA pattern with relatively high S-phase in one. Histopathologically, all diploid and low S-phase neoplasms displayed relatively uniform cellular features and low mitotic counts. All patients are alive and free of disease; one is still alive after a single recurrence. Our data suggest that sinonasal hemangiopericytomas are low-grade neoplasms as evidenced by their histomorphology and their DNA content. Recurrences are delayed and can be controlled.

The E. coli dnaY gene encodes an arginine transfer RNA

The E. coli dnaY gene product is an arginine tRNA. Its 77 nucleotide sequence can be folded into a typical cloverleaf structure with a UCU anticodon corresponding to the rare arginine codon AGA. A dnaY+ plasmid confers overproduction of at least one arginine-accepting minor species of tRNAArg. The dnaY promoter was identified by run-off transcription studies, and the initiating nucleotide was identified by sequencing the 5' end of the in vitro transcript. The primary products in vitro are RNAs of 180 and 190 nucleotides, which presumably are processed in vivo to generate the mature form. Transcription is terminated in vitro, and presumably in vivo, by a rho-dependent process.

An E. coli DNA fragment 118 base pairs in length provides dnaY+ complementing activity

The dnaY gene of E. coli, thought to be involved in the polymerization phase of DNA replication, was localized on a fragment 118 base pairs in length. This fragment, cloned in two different vectors and tested in a dnaY (Ts) recA host, has dnaY + complementing activity. The nucleotide sequence of the 118 base pairs and flanking bases was determined. The dnaY complementing activity was inactivated by transposon insertion and by localized chemical mutagenesis. Three independent insertions of Tn5 into the 118 base pair region eliminated dnaY activity. Eight single-base-change mutations that resulted in loss of dnaY activity also were located within the 118 base pair region. Analysis of the nucleotide sequence reveals a potential promoter but reveals no open reading frames likely to be translated into polypeptides. However, an RNA transcript of the dnaY region is synthesized in vivo. Perhaps the active product of dnaY is a small RNA or perhaps the dnaY region functions as a site.