Well, i deal with clinical trials mainly and not with the vasic lab genes or proteins which i highly believe are as equally significant. I have limited knowledge regarding your question. Thanks for passing by though...

I'd say it's an abandoned practice, but intra-lesional injection of BCG was done many years ago; regarding doses and frequency, I can provide no information, but a single scarification or puncture probably won't hurt, besides the risks of 'systemic infection' with the BCG strain, that may not be too different from those in bladder instillations. 

As mice are the only involved, you can approach the subject of pharmacology of BCG in advanced melanoma same as a Phase I trial, in cohorts of 5 for each schedule, and see what happens.

The 'in situ vaccine' approach we use is one where IL-12 expressing plasmids are electroporated directly into the tumor. Both in  pre-clinical studies using B16.F10 syngeneic mouse models and in clinical trials in melanoma.  Here is a recent abstract on the clinical data from 2017 ASCO-SITC meeting.

J Clin Oncol 35, 2017 (suppl 7S; abstract 78)

Author(s): 

Alain Patrick Algazi, Katy K. Tsai, Michael Rosenblum, Bernard A. Fox, Robert Hans Ingemar Andtbacka, Amy Li, Kathryn Toshimi Takamura, Mary Dwyer, Erica Browning, Reneta Talia, Chris Twitty, Mai H. Le, Sharron Gargosky, Jean S. Campbell, Carmen Ballesteros-Merino, Carlo Bruno Bifulco, Robert Pierce, Adil Daud; University of California, San Francisco Medical Center- Mt. Zion, San Francisco, CA; Division of Hematology/Oncology, University of California, San Francisco, San Francisco, CA; University of California, San Francisco, San Francisco, CA; Earle A. Chiles Research Institute at Providence Portland Medical Center, Portland, OR; Huntsman Cancer Institute, Salt Lake City, UT; Oncosec Medical Inc., San Diego, CA

Abstract: 

Background: Recent publications support the emergence of predictive biomarkers for pembrolizomab in melanoma based on the expression of PD-L1 in the tumor microenvironment (Daud 2016a) or the frequency of PD-1hiCTLA-4hi on CD8+ TIL (Daud 2016b) whereby immunologically inactive tumors show poor response to immune checkpoint inhibition alone. Since intratumoral pIL-12 with electroporation (IT-pIL12-EP) increases TIL in both treated and untreated lesions, we hypothesize that non-response can be rescued with the combination of IT-pIL12-EP and anti-PD-1. Phase II clinical and immunological data are shown. Methods: Melanoma stage III/IV patients were enrolled with CD8+ TIL < 25% PD-1hiCTLA-4+measured by flow cytometry (NCT02493361). PD-L1 IHC (22C3 Ab) was also evaluated. Patients were treated with pembrolizumab (200mg every 3 weeks) and IT-pIL12-EP. Patients were evaluated for ORR every 12 weeks (RECISTv1.1). Pre- and post-treatment blood and tumor specimens were collected, and analyzed for immune phenotyping, gene expression, T cell receptor diversity, and changes in the tumor microenvironment by IHC. Results: TIL assessment for evaluable enrolled patients were < 22% PD-1hiCTLA-4+, a value associated with anti-PD-1 non-response (Daud 2016b). Remarkably, although predicted to be an unresponsive population, the ORR was 40% (4CR/ 2PR) by RECISTv1.1. In patients with CR/PR, analysis of the tumor microenvironment revealed many significant immunological changes not seen in non-responders, including number and ratios of CD8+:PD-L1+by IHC, increased expression of NK, CD8 and ‘adaptive resistance’ markers by NanoString, as well as increased clonality and T cells by TCR sequencing. Conclusions: The excellent safety profile and striking 40% clinical response rate is encouraging as treated patients were predicted to be non-responsive to pembrolizumab. The correlative data shows an immune-directed mechanism that is differentiated between responders and non-responders suggesting the combination can effectively alter the tumor microenviroment to benefit patients otherwise unlikely to respond to anti-PD-1 monotherapy. Clinical trial information: NCT02493361